CURRICULUM GRADE 10 -12 DIRECTORATE NCS (CAPS) TEACHER SUPPORT DOCUMENT GRADE 10 MATHEMATICS STEP AHEAD PROGRAMME 2022 This document has been compiled by the KZN FET Mathematics Subject Advisors. 1 PREFACE This support document serves to assist Mathematics teachers on how to deal with curriculum gaps and learning losses as a result of the impact of COVID-19 since 2020. It also captures the challenging topics in the Grade 10 – 12 work. The lesson plans should be used in conjunction with the 2022 Recovery Annual Teaching Plans. Activities should serve as a guide on how to assess topics dealt with in this document. It will cover the following: TABLE OF CONTENTS TOPICS PAGE NUMBERS 1. ALGEBRA 1 – 58 2. EUCLIDEAN GEOMETRY 59 – 85 3. TRIGONOMETRY 86 – 111 4. ANSWERS 112 - 2 Term Sub-topics 1 TOPIC: ALGEBRA Weighting: (30/100 marks from Paper 1) LESSON 1: NUMBER SYSTEM 1 hour 10 Duration Grade Date Number system. Converting recurring decimals to the form a . b RELATED CONCEPTS/ TERMS/VOCABULARY Real and non-real numbers Rational and irrational numbers Integers, counting numbers and natural numbers Finite, recurring and non-recurring decimals PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Knowledge of the Number System from earlier grades. Knowledge of fractions and decimal fractions from earlier grades. RESOURCES Gr. 10 textbooks : Siyavula; Platinum, Survival Series, Classroom Maths and Mind Action Series The Answer Series 3 in 1 Study Guide for Gr. 10 ERRORS/MISCONCEPTIONS/PROBLEM AREAS 22 That , and therefore a rational number. 7 METHODOLOGY Explain to learners that all numbers are either Real or Non-real. Non-real numbers are e.g. square roots of negative numbers. E.g. Consider 16 . 2 4 2 16 and 4 16 as well. No number, when squared, equals 16 . So: 16 is not a real number. It is Non-real! They are Non-real, because a number a number should have the number itself as answer. And multiplying any number by itself can never have as answer a negative number. As shown in the sketch below Real numbers are made up of Rational numbers ( Q ) and Irrational numbers ( Q) . Rational numbers are either terminating or recurring decimals, and can always be written in the form a , with a and b integers and b 0 . b 3 Terminating (or finite) decimals: E.g. 3 0,75 (the decimals stop at some point, in this case at the 4 second decimal). 1 0,3333333.... 0,3 3 5 0,1515151515.... 0,1 5 33 275 0,275275275275275.... 0,2 75 999 2 0,13333333....... 0,13 15 (the decimals continue, but there is a recurring pattern in the decimal expansion) Included under Rational numbers are: Integers (Z) = ..... 3; 2 1; 0 ; 1; 2 3 ..... Included under Integers are: Counting numbers ( N 0 ) = 0 ; 1; 2 3 ..... Recurring decimals: E.g. Included under Counting numbers are: Natural numbers (N) = 1; 2 3 ..... Irrational numbers are non-terminating and non-recurring decimals, and cannot be written in the form a , with a and b integers and b 0 . Examples are surds and . b E.g. 6 2,449489743..... 3,141592654..... (no recurring pattern in the decimal expansion) Irrational numbers do exist (i.e. they are real), but one can only get an approximate value for them. The decimals just go on and on. a How to convert an infinite recurring decimal to the form : b Example 1: 0,5 0,5 0,555555555555555........ Let x 0,555555555555555........ Line 1 Then: Line 2 10x 5,555555555555555........ 9x 5 Line 2 – Line 1: 5 x 9 The question could also have been: Show that 0,5 is a rational number. Example 2: 0,1 8 0,1 8 0,181818181818....... Let x 0,18181818181818....... Then: 100x 18,18181818181818....... Line 2 – Line 1: 99 x 18 18 2 x 99 11 Line 1 Line 2 4 ACTIVITIES/ASSESSMENTS 1.1.1 Classify the following numbers by placing a tick in the appropriate column(s): N0 Non-real Real Irrational Rational Integer N 5 –2 4,1 1 2 3 0,7 9 3 8 10 1 9 16 8 3 8 3 9 0 5 5 0 1.1.2 Write each recurring decimal in the form (a) (b) (c) 0,2222222....... 0,27272727....... 0,7 a : b (d) (e) (f) 0,2 13 0,1 5 0,54 5 TOPIC: ALGEBRA Weighting: (30/100 marks from Paper 1) LESSON 2: SURDS AND PRODUCTS 1 hour 10 Duration Grade 1 Term Date To establish between which two integers a given simple surd lies. Products of Algebraic expressions: Revision of Gr. 9 work. RELATED CONCEPTS/ TERMS/VOCABULARY Surd Perfect square Monomial, binomial and trinomial Like terms PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Multiplication of monomials and binomials. Adding like terms. RESOURCES Gr. 10 textbooks : Siyavula; Platinum, Survival Series, Classroom Maths and Mind Action Series The Answer Series 3 in 1 Study Guide for Gr. 10 ERRORS/MISCONCEPTIONS/PROBLEM AREAS Leaving out the middle term when determining the product of two binomials, e.g. to say that a b2 a 2 b 2 Sub-topics METHODOLOGY To establish between which two integers a given simple surd lies: o Example: the surd 40 . o Search for the highest perfect square below 40. Also: search for the first perfect square above 40. To do that learners can list the perfect squares: 12 1 2 2 4 32 9 42 16 52 25 o So: 40 lies between 6 2 36 and 7 2 49 . 62 36 7 2 49 o Therefore: 62 40 7 2 And: 6 40 7 (taking square roots throughout) Revision of Gr. 9 work on products of algebraic expressions: First explain/revise the methods for monomial binomial and binomial binomial: o a b c abc [Just one term as answer] o a b c ab bc [The distributive law (can check the correctness of the answer by substituting random values of a, b and c in the LHS and the RHS).] o a b c d a b c a b d [Still the Distributive law] ac bc ad bd [Four terms in the answer] o Product of two binomials can also be done using the FOIL method: F: firsts; O: outers; I: inners; L: lasts. O F I L This method has the advantage that the like terms, if any, will be next to each other and it will be easy to add them. 6 E.g.: 4 x 2 y 3x y 12 x 2 6 xy 4 xy 2 y 2 12 x 2 10 xy 2 y 2 Even when squaring binomials this same method may be used – just write the same bracket twice, to make it easier to see what to do. Learners are now given an exercise to consolidate gr. 9 skills before progressing to gr. 10 content. ACTIVITIES/ASSESSMENTS 1.2.1 (a) (b) (c) 1.2.2 (a) (b) (c) (d) (e) (f) (g) (h) (i) Between which two integers do each of the following surds lie? 7 70 10 Expand and simplify the following: 4 x2 x 3 x5 x 1 2 x6 x 2 x 8 x 5x 4 x 5x 4 x 5x 4 7 x 12 x 3 x 3 y 4 x 6 y (j) (k) (l) (m) (n) (o) (p) (q) 5 x 25 x 2 4a 3b 4a 3b x 42 a 3b2 2a 5b 2 2 32 x y 2m 4n2 2 x 3 y 3x 2 y 4 2 4 2 1 1 x x 2 3 7 1 Term TOPIC: ALGEBRA Weighting: (30/100 marks from Paper 1) LESSON 3: PRODUCTS CONTINUED 1 hour 10 Duration Grade Date Products of Algebraic expressions: Binomial multiplied by trinomial. Mixed exercise on products. RELATED CONCEPTS/ TERMS/VOCABULARY Monomial, binomial and trinomial Like terms PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Multiplication of monomials and binomials. Adding like terms. RESOURCES Gr. 10 textbooks : Siyavula; Platinum, Survival Series, Classroom Maths and Mind Action Series The Answer Series 3 in 1 Study Guide for Gr. 10 ERRORS/MISCONCEPTIONS/PROBLEM AREAS To leave out brackets where they are needed, e.g. to write x 2 x 3x 1 x 2 x 2 4 x 3 4 x 3 , instead of x 2 x 3x 1 x 2 x 2 4 x 3 4 x 3 . Sub-topics METHODOLOGY The product of a binomial and a trinomial: a b c d e ac d e bc d e ac ad ae bc bd be Six terms in the answer, but where there are like terms, they can be combined. Example: like terms indicated x 3x 2 x 2 x 3 x 2 2 x 3x 2 3x 6 x3 2x 2 x 6 It is very important that learners get enough practice in determining products, and to ensure that they are exposed to different types, also to those where there are more than one product in an expression (as in 1.3.2 below). ACTIVITIES/ASSESSMENTS 1.3.1 (a) Expand and simplify: x 1x 2 x 2 (g) a b3 x y x 2 xy y 2 x 3 y x 2 3xy 9 y 2 x 4 x 2 5 y x 2 5 y (e) (d) 3c 22c 2 3c 1 x 2 y 3x 2 xy 2 y 2 a ba b2 1.3.2 (a) Expand and simplify the following: 5 y 12 3 y 42 3 y (d) (b) 2 x y 2 3x 2 y 2 x 4 y x 4 y (e) (c) 8m 3n 4m n n 3m n 3m (f) (b) (c) (f) 2 1 x x 2 3 x x x x 8 Term TOPIC: ALGEBRA Weighting: (30/100 marks from Paper 1) LESSON 4: FACTORISATION: REVISION OF GR. 9 FACTORISATION 1 1 hour 10 Duration Date Grade Factorisation: Revision of Gr. 9 work: Common factor and Difference between two squares. RELATED CONCEPTS/ TERMS/VOCABULARY Factorisation and determining a product as opposite/reverse processes. PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Multiplication of monomials and binomials. RESOURCES Gr. 10 textbooks : Siyavula; Platinum, Survival Series, Classroom Maths and Mind Action Series The Answer Series 3 in 1 Study Guide for Gr. 10 ERRORS/MISCONCEPTIONS/PROBLEM AREAS To attempt to factorise the sum of two squares. METHODOLOGY Factorisation is the opposite/reverse process of determining a product. 4 x 3 4 x 12 E.g.: Sub-topics x 3x 2 x 2 5x 6 FACTORS → TERMS (multiplying) FACTORS ← TERMS (factorisation) Factorisation Method 1: Taking out a common factor: E.g.: 3x 2 6 x Determine the highest common factor between the terms, namely 3 x , and we can take this out as a . common factor and create a bracket: 3x 2 6 x 3x To determine what has to be written in the bracket, divide (reverse of multiply) each term by the common factor: 3x 2 6 x 3xx 2 . After factorising: Take your final answer, multiply out and check to see if you get what you have started with. Factorisation Method 2: Difference between two squares: When learners were calculating products, they had some examples of the type: a ba b a 2 ab ab b 2 a 2 b 2 . The outers and inners (from FOIL) cancel each other and the middle term therefore falls away. In the reverse (i.e. factorisation): The factors of a 2 b 2 a b a b . In other words, the factors of the difference between two perfect squares are 1st term 2nd term 1st term 2nd term . Very important: Always first check if an expression contains a common factor before attempting any other method of factorisation. ACTIVITIES/ASSESSMENTS 1.4.1 Factorise the following: 3x 15 (a) (f) 9a 2 25b 2 (b) 16a 4b8 8ab7 36a 2b3 (g) 12a 2 3b 2 k 2 p2 (c) (h) x4 1 9 1 2 1 2 (d) (i) x2 2 x y x 4 81 2 2 2 x y x y (e) 9 Term Sub-topics 1 TOPIC: ALGEBRA Weighting: (30/100 marks from Paper 1) LESSON 5: FACTORISING TRINOMIALS 2 hours 10 Duration Grade Date Factorisation: Trinomials. RELATED CONCEPTS/ TERMS/VOCABULARY Factorisation Trinomials PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Determining all the different pairs of factors of a specific number. Factorisation of trinomials of the format x 2 bx c . RESOURCES Gr. 10 textbooks : Siyavula; Platinum, Survival Series, Classroom Maths and Mind Action Series The Answer Series 3 in 1 Study Guide for Gr. 10 ERRORS/MISCONCEPTIONS/PROBLEM AREAS Not being able to determine the relevant pairs of factors of a and c in ax 2 bx c . Not multiplying out after factorisation to ensure that the factors are correct. METHODOLOGY Factorisation Method 3: Trinomials. Factorisation of trinomials of the format x 2 bx c is taught in Gr. 9, but should be revised with learners in Gr. 10. In Gr. 10 factorisation of trinomials is taken further to also include those of the format ax 2 bx c , where a 1 . A worksheet to guide learners in the factorisation of both these types of trinomials is included with this lesson plan (Activity 1.5.1). After completion of the worksheet, teachers should go through the examples in the worksheet with their learners, re-enforcing the concepts and skills therein and then give them a comprehensive exercise to do on this topic. (Could start with Activity 1.5.2) 10 ACTIVITIES/ASSESSMENTS Activity 1.5.1: GRADE 10 MATHEMATICS WORKSHEET – FACTORISING TRINOMIALS PART A: Factorising 𝒂𝒙𝟐 + 𝒃𝒙 + 𝒄, with 𝒂 = 𝟏: 1. The formula 𝑎𝑥 2 + 𝑏𝑥 + 𝑐 represents a general quadratic expression. Given: the quadratic expression 𝑥 2 + 3𝑥 + 2. In this case: 𝑎 = 1. 1.1 Write down the values of 𝑏 and 𝑐. …………………………………………………………………………………… 1.2 Determine the integers m en n for which 𝑚 × 𝑛 = 𝑐 and 𝑚 + 𝑛 = 𝑏. …………………………………………………………………………………… 1.3 Use the values of 𝑚 and 𝑛 (from 1.2) to form the algebraic expression x m x n . …………………………………………………………………………………… 1.4 Determine the product of your answer to 1.3. …………………………………………………………………………………… 1.5 Compare the given quadratic expression to your answer to 1.4. What do you notice? …………………………………………………………………………………… The steps in question 1 describe a method of factorising an expression of the format 𝑥 2 + 𝑏𝑥 + 𝑐. We determine integers m and n such that x 2 bx c x m x n . x m and x n are factors of the expression x 2 bx c . 2. Factorise the following expressions where b and c are positive. 2.1 𝑥 2 + 5𝑥 + 6 = …………………………………………………………………… 2.2 𝑥 2 + 8𝑥 + 12 = …………………………………………………………………. 2.3 𝑥 2 + 7𝑥 + 12 = …………………………………………………………………. 2.4 Comment on the signs of 𝑚 and 𝑛. ……………………………………………. 3. Factorise the following expressions where b is negative and c is positive. 3.1 𝑥 2 − 5𝑥 + 6 = ………………………………………………………………….. 3.2 𝑥 2 − 3𝑥 + 2 = ………………………………………………………………….. 3.3 𝑥 2 − 8𝑥 + 15 = ………………………………………………………………… 3.4 Comment on the signs of 𝑚 and 𝑛. ……………………………………………. 3.5 Compare the signs of 𝑚 and 𝑛 with that of 𝑏. ……………………………….. 11 4. Factorise the following expressions where b is positive and c is negative. 5. 4.1 x 2 x 12 ……………………………………………………………………. 4.2 x 2 5 x 6 …………………………………………………………………… 4.3 x 2 2 x 15 ……………………………………………………………………. 4.4 Comment on the signs of 𝑚 and 𝑛. ……………………………………………. Factorise the following expressions where b and c are negative. 5.1 x 2 x 2 …………………………………………………………………….. 5.2 x 2 x 12 ……………………………………………………………………. 5.3 x 2 3 x 10 …………………………………………………………………… 5.4 Comment on the signs of 𝑚 and 𝑛. …………………………………………….. 6. Using your answers to 2.4 and 3.4: what do you observe about the signs of m and n when c is positive? ……………………………………………………………………. 7. Using your answers to 4.4 and 5.4: what do you observe about the signs of m and n when c is negative? ……………………………………………………………. 8. Using your answers to questions 4 and 5: which one of m and n has the same sign as b? The bigger one, or the smaller one? ………………………………………… 9. Complete the summary below by choosing the correct word: While factorising the quadratic expression 𝑎𝑥 2 + 𝑏𝑥 + 𝑐, with 𝑎 = 1: 9.1 If c is positive, the signs in the two brackets are (the same / different). 9.2 If the signs in the brackets are different, then the bigger one of m and n will have the sign of (the middle term b / the last term c). 12 PART B: Factorising 𝒂𝒙𝟐 + 𝒃𝒙 + 𝒄, with 𝒂 ≠ 𝟏: We now need to pay attention to the possible factors of both a and c, and not only those of c, as was the case in Part A . TYPE 1: Factorising 𝒂𝒙𝟐 + 𝒃𝒙 + 𝒄, where both b and c are positive. Trinomial no. 1: 𝟐𝒙𝟐 + 𝟏𝟑𝒙 + 𝟐𝟏: Possible factors of 2𝑥 2 are 2𝑥 and 1𝑥. Possible factors of 21 are 7 and 3; or 21 and 1. Which combination of factors of 2𝑥 2 and 21 will lead to the correct factorisation of 2𝑥 2 + 13𝑥 + 21? The different possible combinations are: (2𝑥 + 7)(1𝑥 + 3); (2𝑥 + 3)(1𝑥 + 7); (2𝑥 + 21)(1𝑥 + 1) and (2𝑥 + 1)(1𝑥 + 21). Now, multiply out each of these products: (2𝑥 + 1)(1𝑥 + 21) = …………………………………………………………………………………. (2𝑥 + 3)(1𝑥 + 7) = ……………….…………………………………………………………………. (2𝑥 + 21)(1𝑥 + 1) = …………………………………………………………..……………..………. (2𝑥 + 7)(1𝑥 + 3) = ……………………….…………………………………………………..………. All four these products give the correct first and third terms, namely 2𝑥 2 and 21, but only one gives the correct middle term of 13𝑥, and is therefore the correct factorisation. In this case there were only four possibilities to choose from. In many other instances there are many more possibilities and it is not practical to write them all down and multiply out again to check. We need a shorter method. Trinomial no. 2: 15𝑥 2 + 19𝑥 + 6: 𝟑𝒙 𝟓𝒙 𝟓𝒙 𝟑𝒙 different possible factors of: 𝟏𝟓𝒙 𝟏𝒙 𝟏𝒙 𝟏𝟓𝒙 15𝑥 2 6 1 3 2 6 Now try different combinations, in search of the correct middle term of 19𝑥: E.g.: 𝟑𝒙 6 i.e. factorising as (3𝑥 + 6)(5𝑥 + 1) 𝟓𝒙 1 However, this gives a middle term of 3𝑥 + 30𝑥 = 33𝑥, which is not correct. More combinations can be tried. Another combination will be: 𝟓𝒙 3 i.e. factorising as (5𝑥 + 3)(3𝑥 + 2) 𝟑𝒙 2 This combination gives a middle term of 10𝑥 + 9𝑥 = 19𝑥, which is correct; and therefore this factorisation is correct. 13 Trinomial no. 3: 𝟓𝒙𝟐 + 𝟐𝟖𝒙 + 𝟏𝟓: 𝟓𝒙 𝟏𝒙 different possible factors of: 𝟏𝒙 𝟓𝒙 5𝑥 2 15 1 5 3 15 Now try different combinations, in search of the correct middle term of 28𝑥: E.g.: 𝟓𝒙 15 i.e. factorising as (5𝑥 + 15)(1𝑥 + 1) 𝟏𝒙 1 However, this gives a middle term of 5𝑥 + 15𝑥 = 20𝑥, which is not correct. More combinations can be tried. Another combination will be: 𝟏𝒙 5 i.e. factorising as (𝑥 + 5)(5𝑥 + 3) 𝟓𝒙 3 This combination gives a middle term of 25𝑥 + 3𝑥 = 28𝑥, which is correct; and therefore this factorisation is correct. Trinomial no. 4: 𝟕𝒙𝟐 + 𝟐𝟕𝒙 + 𝟏𝟖: Now factorise this trinomial in a similar way: ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………... 14 TYPE 2: Factorising 𝒂𝒙𝟐 + 𝒃𝒙 + 𝒄, where b is negative and c is positive. Trinomial no. 1: 𝟐𝒙𝟐 − 𝟏𝟑𝒙 + 𝟐𝟏: 𝟐𝒙 𝟏𝒙 7 𝟏𝒙 3 21 1 2𝑥 2 different possible factors of: 𝟐𝒙 𝟏𝒙 𝟐𝒙 7 3 21 From above: 6𝑥 + 7𝑥 = 13𝑥. But to get a middle term of −13𝑥, the factors will be: (2𝑥 − 7)(𝑥 − 3). Trinomial no. 2: 𝟓𝒙𝟐 − 𝟐𝟖𝒙 + 𝟏𝟓: Now factorise this trinomial in a similar way: …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… …………………………………………………………………………………………………………… ………………………………………………………………………………………………………... TYPE 3: Factorising 𝒂𝒙𝟐 + 𝒃𝒙 + 𝒄, where b is positive and c is negative. Trinomial no. 1: 𝟐𝒙𝟐 + 𝒙 − 𝟐𝟏: To obtain the −21 (a negative number) for the last term, the signs in the two brackets have to be different, the one positive and the other negative. 𝟐𝒙 𝟏𝒙 different possible factors of: 𝟐𝒙 7 𝟏𝒙 3 𝟏𝒙 𝟐𝒙 2𝑥 2 21 1 7 3 21 7𝑥 − 6𝑥 = 1𝑥 Attempting to factorise: 2𝑥 2 + 𝑥 − 21 = (2𝑥 7)(1𝑥 3) To get a middle term of +𝑥, it will have to be: (2𝑥 + 7)(1𝑥 − 3). Trinomial no. 2: 𝟕𝒙𝟐 + 𝟏𝟔𝒙 − 𝟏𝟓: Now factorise this trinomial in a similar way: ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………... 15 TYPE 4: Factorising 𝒂𝒙𝟐 + 𝒃𝒙 + 𝒄, where both b and c are negative. Trinomial no. 1: 𝟐𝒙𝟐 − 𝟏𝟏𝒙 − 𝟐𝟏: To obtain the −21 (a negative number) for the last term, the signs in the two brackets have to be different, the one positive and the other negative. 𝟐𝒙 𝟏𝒙 2𝑥 2 different possible factors of: 𝟏𝒙 7 𝟐𝒙 3 𝟏𝒙 𝟐𝒙 21 1 7 3 21 3𝑥 − 14𝑥 = −11𝑥 Attempting to factorise: 2𝑥 2 + 𝑥 − 21 = (𝑥 7)(2𝑥 3) To get a middle term of −11𝑥, it will have to be: (𝑥 − 7)(2𝑥 + 3). Trinomial no. 2: 𝟒𝒙𝟐 − 𝟗𝒙 − 𝟗: Now factorise this trinomial in a similar way: ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… Activity 1.5.2: Factorise the following: p 2 8 p 15 (a) (l) 2a 2 7a 3 (b) p 2 8 p 15 (m) 2a 2 13a 15 (c) p 2 2 p 15 (n) 4 y 2 12 y 5 (d) p 2 2 p 15 (o) 6a 2 13ab 6b 2 (e) x 2 7 x 10 (p) 12x 2 x 6 (f) 2a 2 14a 20 (q) 8 x 2 14 xy 15 y 2 (g) b 2 3b 10 (r) 22 y 2 9 y 1 (h) y 2 3 y 10 (s) 3 2x x2 (i) a 2 5a 84 (t) a 2 10a 25 (j) x 2 26a 48 (u) 4 p2 4 p 1 (k) 2 x 2 5x 3 (v) 9a 2 30ab 25b 2 16 1 Term TOPIC: ALGEBRA Weighting: (30/100 marks from Paper 1) LESSON 6: FACTORISATION BY GROUPING IN PAIRS 1 hour 10 Duration Date Grade Sub-topics Factorisation: Grouping in pairs. RELATED CONCEPTS/ TERMS/VOCABULARY Switch around Ratio PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Factorisation by means of taking out a common factor RESOURCES Gr. 10 textbooks : Siyavula; Platinum, Survival Series, Classroom Maths and Mind Action Series The Answer Series 3 in 1 Study Guide for Gr. 10 ERRORS/MISCONCEPTIONS/PROBLEM AREAS To incorrectly leave out the + or – sign in the second line: ax bx ay by xa b y a b xa b y a b instead of x y a b METHODOLOGY Factorisation Method 4: Grouping in Pairs: Sometimes when we have 4 terms, we need to group them before we can factorise: ax bx ay by xa b y a b [Take out x as common factor from the 1st two terms and y from the last two terms.] a b [ x y ] [Now take a b out as common factor.] Some “switch arounds”: o From b a to a b : a b b a , therefore xa b y b a xa b y a b a b x y o From b a to a b : b a a b , therefore xa b y b a xa b y a b a b x y o From ay by to ay by : ay by y a b , therefore ax bx ay by xa b y a b a b x y The first step is to decide on the pairs of terms to group. A useful hint is to observe the ratio of the coefficients. The ratio of the coefficients in the two pairs has to be the same. E.g. 5 : 3 = 10 : 6. Examples: o 4 x 2 8 x 2a ax 4 x 2 8 x ax 2a [ratios: 4 : 8 = 1 : 2] 4 x x 2 a x 2 4 x a x 2 o 2ac 6bd 3ad 4bc 2ac 3ad 4bc 6bd [ratios: 2 : 3 = 4 : 6] a 2c 3d 4bc 6bd a 2c 3d 2b2c 3d a 2b 2c 3d ACTIVITIES/ASSESSMENTS 1.6.1 Factorise the following: mx my nx ny (a) (d) (b) mp mq p q (e) (c) x 4 y 3ax 12ay (f) 6bx 15cx 10cy 4by 6 x 2 12ac 9ax 8cx ac cd ab2 b 2 d 17 TOPIC: ALGEBRA Weighting: (30/100 marks from Paper 1) LESSON 7: FACTORISATION: SUM AND DIFFERENCE OF CUBES 1 2 hours 10 Duration Date Grade Term Factorisation: Sum and difference of cubes. Factorisation: A mixed exercise to consolidate factorisation skills. RELATED CONCEPTS/ TERMS/VOCABULARY Cubes Factorisation PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Multiplication of a binomial by a trinomial RESOURCES Gr. 10 textbooks : Siyavula; Platinum, Survival Series, Classroom Maths and Mind Action Series The Answer Series 3 in 1 Study Guide for Gr. 10 ERRORS/MISCONCEPTIONS/PROBLEM AREAS Because the sum of cubes can be factorised some learners attempt to also factorise the sum of squares. Sub-topics METHODOLOGY Factorisation Method 5: Sum and Difference of Cubes: As introduction give learners the following products to multiply out: o x y x 2 xy y 2 o o They should obtain the following answers: o x y x 2 xy y 2 x 3 y 3 o x y x 2 xy y 2 2 x 3 y 4 x 2 6 xy 27 y 2 x y x 2 xy y 2 x 3 y 3 2 x 3 y 4 x 2 6 xy 27 y 2 8 x 3 27 y 3 o Remind learners that factorisation is the reverse process of multiplication; and give them the challenge to use the products they have just calculated and to come up with a “method” to factorise the sum and difference of cubes. Guide them a bit if necessary to obtain the following method: o From x 3 y 3 x y x 2 xy y 2 (first)3 +(last)3 =(first + last) [(first)2 – (first)(last) + (last)2 ] where first = x and last = y o From x 3 y 3 x y x 2 xy y 2 (first)3 – (last)3 =(first – last) [(first)2 + (first)(last) + (last)2 ] again: first = x and last = y Learners will now be given an exercise to practice factorising the sum and difference of cubes. Thereafter: the teacher will remind learners of the different methods of factorisation, and then give them a mixed factorisation exercise to do, requiring them in each case to decide for themselves which method(s) to use. 18 ACTIVITIES/ASSESSMENTS 1.7.1 Factorise the following: (a) x3 1 (d) 64x 3 125 (b) 1 8y3 (e) 2 x 3 16 y 6 (c) a 3 27b3 (f) 5a 9 5b9 1.7.2 Factorise completely: (a) x 2 x 12 (g) 16 p 2 56 p 49 (b) 5a 2 80 (h) ax 2 3by 2 3bxy axy (c) 12 x 2 19 xy 21y 2 (i) x2 2 (d) 4b3 8b 2 ab 2a (j) x2 8 (e) x3 1000 3 1000 y (k) x6 y6 (f) y 3 y 2 y 1 (l) 36x 2 100 1 4 16 x2 19 Term 1 TOPIC: ALGEBRA Weighting: (30/100 marks from Paper 1) LESSON 8: SIMPLIFICATION OF ALGEBRAIC FRACTIONS 1 hour 10 Duration Date Grade Simplification of Algebraic fractions. Multiplication and Division of Algebraic fractions. RELATED CONCEPTS/ TERMS/VOCABULARY Factors and terms PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Ability to simplify, multiply and divide fractions. RESOURCES Gr. 10 textbooks : Siyavula; Platinum, Survival Series, Classroom Maths and Mind Action Series The Answer Series 3 in 1 Study Guide for Gr. 10 ERRORS/MISCONCEPTIONS/PROBLEM AREAS In a fraction identical factors may be cancelled out; but not identical terms. Sub-topics METHODOLOGY Simplifying fractions: o Discuss with the learners how (whether) the following two fractions can be simplified: ab ab and . b b ab b a 1 a , because 1 . b b Conclusion: identical factors in the numerator and denominator may be cancelled out. ab In the case of the two b’s may not be “cancelled out”, because there are two terms in b the numerator and both of them have to be divided by b. Conclusion: identical terms in the numerator and denominator may not be cancelled out. ab a b a [Note: could also be rewritten as 1 .] b b b b o If there is more than one term in the numerator of an algebraic fraction, the strategy most of the time will be to factorise the numerator and then to cancel identical factors in the numerator and denominator. o Examples: 4 x 2 10 x 2 x2 x 5 4 x 2 10 x 4 x 2 10 x 2 x 5 or 2x 5 2x 2x 2x 2x 2x 4 x 2 1 2 x 12 x 1 2 x 1 2 x2 x 1 2x 4x 2 2x 20 Multiplying and dividing algebraic fractions: a c ac o Multiplication: . b d bd a c a d ad o Division: b d b c bc o Examples: p2 p 2 6 3 p 2p 4 2 p p 2 p 1 32 p 2 p 2 2 p p 2 p 1 3 p 2 [See “switch arounds” in Lesson 6.] 2 p 2 p2 3 p 1 2 3x 9 y 3 2 x 5 4 x 10 3x 3 y 4 x 10 2x 5 3 3x 3 y 22 x 5 2x 5 3 2 x 3 y ACTIVITIES/ASSESSMENTS 1.8.1 (a) (b) (c) (d) Simplify: 4x2 y 2 2 y 2 2 y2 6x2 x 1 3x 2 5 x 2 8a 3 27 6a 2 27a 27 (e) (f) (g) x 2 x 6 x 2 16 2 2x 8 x 2x 2k 2 k 6 k 4 9 2k 3 k 2 2k 2 6 3x 2 3 x 2 y xy 2 y 3 2 y 2 2 xy 2 y 2 x2 1 x 2 10 x 5x x 1 21 Term Sub-topics TOPIC: ALGEBRA Weighting: (30/100 marks from Paper 1) LESSON 9: ADDING AND SUBTRACTING ALGEBRAIC FRACTIONS 1 2 hours 10 Duration Date Grade Adding and Subtracting Algebraic fractions. RELATED CONCEPTS/ TERMS/VOCABULARY Lowest common denominator (LCD) PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE All the different methods of factorising algebraic expressions. Adding and subtracting fractions. Determining the lowest common denominator of numbers and of algebraic expressions. RESOURCES Gr. 10 textbooks : Siyavula; Platinum, Survival Series, Classroom Maths and Mind Action Series The Answer Series 3 in 1 Study Guide for Gr. 10 ERRORS/MISCONCEPTIONS/PROBLEM AREAS Not using brackets after a minus sign. METHODOLOGY Revise the process of adding and subtracting fractions in which no variables occur: 1 1 Example: : 2 3 First step is to write them as equivalent fractions, i.e. with the same denominator. For that purpose we need the lowest common denominator, i.e. the smallest number that both 2 and 3 can divide into, in this case 6. 1 3 1 2 and 2 6 3 6 1 1 3 2 5 3 2 3 2 Therefore: . [ can also be written as ] 6 6 2 3 6 6 6 6 1 1 3 2 1 Similarly: 2 3 6 6 6 22 Adding and subtracting algebraic fractions: The same steps and reasoning can now also be applied to adding and subtracting algebraic fractions: 5 3 2 2 o LCM of 4x, x 2 and 5 = 20x 2 4x x 5 25x 60 8x 2 This step could be left out. 2 20 x 2 20 x 2 20x Shortcut way from 1st line: divide e.g. 4x into 20x 2 ; 2 25x 60 8 x answer is 5x, multiply by the numerator: 5 x 5 , and 20 x 2 get the new numerator: 25x o 8 x 2 25x 60 20 x x2 3 2 2x 2 x 1 x2 3 2 x 1 x 1 x 1 x 2x 1 6 2x 1x 1 x 2 3x 2 6 2x 1x 1 x 2 3x 8 2x 1x 1 LCM of 2 x 1 and x 1 x 1 is 2 x 1 x 1 For numerator: divide e.g. 2 x 1 into 2 x 1 x 1 ; answer is x 1 , multiply by x 2 , and get the new numerator: x 1 x 1 . ACTIVITIES/ASSESSMENTS 1.9.1 Write as a single fraction and simplify as far as possible: 3 2 x 3 x 2 x 1 2 (a) (e) 2 4a 9 4a 4a 3 3 2 6 3 a a3 a x y (b) (f) 2 3 4 2a a 8a a2 y x 1 2 1 2 3 4 2 2 (c) 1 2 3 (g) 2 2 a ab b a a ab x x x (d) 2a 2a 2 3b 2 3b 3b 6ab 4a (h) x y 1 2 3 3 x y x y2 23 Term 1 Sub-topics TOPIC: ALGEBRA Weighting: (30/100 marks from Paper 1) LESSON 10: EXPONENTIAL LAWS 1 hour 10 Duration Grade Date Revision of the exponential laws and definitions RELATED CONCEPTS/ TERMS/VOCABULARY Grade 8 and 9 exponents PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Definition of the exponent. Laws of exponents RESOURCES Textbooks: Mind Action Series; Answer Series and Study and Master study guide Previous question papers. ERRORS/MISCONCEPTIONS/PROBLEM AREAS Incorrect use of exponential laws: e.g. 23.32 632 65 METHODOLOGY 1. Revision of laws of exponents done in grade 9 and other lower grades. 2. Examples will be done for each law to ensure that learners understand and know how that law can be applied: Laws of Exponents: When multiplying powers with equal bases, keep the base the same and add the exponents: Multiplying powers with equal bases: 𝑥 𝑚 × 𝑥 𝑛 = 𝑥 𝑚+𝑛 𝑥, 𝑦 > 0; 𝑚, 𝑛 ∈ 𝑍 e.g. 23 × 22 = 23+2 = 25 When dividing powers with equal bases, keep the base the same and subtract the denominator exponent from the numerator exponent: Dividing powers with equal bases: 𝑥 𝑚 ÷ 𝑥 𝑛 = 𝑥 𝑚−𝑛 𝑥, 𝑦 > 0; 𝑚, 𝑛 ∈ 𝑍 e.g. 23 ÷ 22 = 23−2 = 21 When raising a base with one power to another power, keep the base the same and multiply the exponents. Power of a power: (𝑥 𝑚 )𝑛 = 𝑥 𝑚𝑛 𝑥, 𝑦 > 0; 𝑚, 𝑛 ∈ 𝑍 e.g. (23 )2 = 23×2 = 26 When multiplying different powers that have the same exponent: Multiplying powers with the same exponents: 𝑥 𝑚 × 𝑦 𝑚 = (𝑥𝑦)𝑚 𝑥, 𝑦 > 0; 𝑚, 𝑛 ∈ 𝑍 e.g. 23 × 33 = (2.3)3 = 63 = 216 24 Definitions: Negative exponents: 1 𝑥 −𝑛 = 𝑥 𝑛 , 𝑥 ≠ 0 1 1 e.g. 2−3 = 23 = 8 Power with exponent zero: 𝑥 0 = 1, 𝑥 ≠ 0 e.g. 20 = 1 Other Rules: 1𝑛 = 1 × 1 × 1 × … … . (𝑛𝑡𝑖𝑚𝑒𝑠) = 1 e.g. 1365 = 1 (−𝑎)𝑛 = 𝑎𝑛 if 𝑛 is even e.g. (−2)4 = 24 = 16 (−𝑎)𝑛 = −𝑎𝑛 if 𝑛 is odd e.g. (−2)3 = −23 = −8 1.10 ACTIVITIES/ASSESSMENTS Classwork Activity 1.10.1 Complete: 23 24 a) b) 22 x 3 32 x 3 c) 53 52 d) 23 x 22 x e) 4x y f) 5x 4x g) 5 x0 2 x 2 3 2 2 0 Homework Activity 1.10.2 Simplify: a) b) 34 5.35 817.84 .4 125 5 .3 .3 3. 312 4 c) d) e) 2 2 7 2 154 9 x 1 32 x.81 18 x.8 x 1 9 x 1.42 x 1 25 TOPIC: ALGEBRA Weighting: (30/100 marks from Paper 1) LESSON 11: EXPONENTIAL LAWS (CONTINUED) 1 hour 10 Duration Date Grade 1 Term Multiplication and division Sub-topics RELATED CONCEPTS/ TERMS/VOCABULARY Laws of exponents PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Addition and subtraction of exponents RESOURCES Textbooks : Mind Action Series; Answer Series and Study and Master study guide Previous question papers METHODOLOGY Few examples will be done on the board with the learners. Examples : 1. Multiplication bases variables a b .a b ab a 4 2 3 2 4 3 4 3 6 a8b 4 .a 4 b3 a 4 b12 a 2 a12 b7 a 2 b12 a12 2 b7 12 a10 b 5 a10 b5 2. Multiplication bases numerical 182 n 1.9 2 .16n 1 1. 81n 3.64n 2 3 .2 .3 . 2 3 . 2 2 2 n 1 4 2 n 3 1. 2 6 4 n 1 n2 34 n 2 22 n 1.3.24 n 4 34 n 12.26 n 12 26 n 3.34 n 3 26 n 12.34 n 12 2 6 n 3 6 n 12 4 n 3 4 n 12 .3 215.315 15 3 215 2 315 26 3. Multiplication bases combined 1 1 27 m 1 3 m 3 81m 2 1 2 1 1 3 m 1 3 m 3 3 4 1 4 2 2 3 m 4 1 4 3m 3 m 3 32 m 1 1 4 1 31 2.m 3 3 33 m 2 1.11 ACTIVITIES/ASSESSMENTS Classwork Activity 1.11.1: Simplify the following expressions: a) 2 xy 3 x y x y 2 xy 2 2 b) c) 2 2 2 1 2 3 9 x 1.12 x 1 27 x.4 x 1 10 x.25 x 1.2 50 x 1.5 x Homework Activity 1.11.2: Simplify the following expressions: a) 9n.12n 1 4.6n b) 2n 2.4n 3 8n 2 c) 4 x 1.8 x 1 16 x 2 27 TOPIC: ALGEBRA Weighting: (30/100 marks from Paper 1) LESSON 12: EXPONENTIAL LAWS (CONTINUED) 1 hour 10 Duration Date Grade 1 Term Exponents that are fractions Sub-topics RELATED CONCEPTS/ TERMS/VOCABULARY Laws of exponents RESOURCES Textbooks : Mind Action Series; Answer Series and Study and Master study guide Previous question papers METHODOLOGY Examples will be done on the board for learners: 3 3 1 1 1 1. 3 2 8 2 1 4 1 2. 81 34 4 3 1 3 2 4x x 1 2 x 3 1 3 2 2 x x 3. 2 1 2 x 3 3 1 2x 2 2 2x 3 3 x x 4 2x 28 1.12 ACTIVITIES/ASSESSMENTS Classwork: Activity 1.12.1: Simplify: 1 a) 27 3 b) 125 3 1 c) 64 d) 1 6 1 2 2 1 4 4 2 9x . x 4 16a . x e) x 6 3 1 f) 27 y 6 3 y 1 Homework Activity 1.12.2: Simplify: 1 2 2 a) 36 x 3x 1 1 b) 64 x6 3 3x 1 1 c) 125m 3 13 25. m 2 1 d) 49 x 2 4 1 3 2 7 .x 3 2 12 9 x . x e) 2 12 3x 1 3 2 13 x x 2 16 x 1 3 9 f) 1 2 29 TOPIC: ALGEBRA Weighting: (30/100 marks from Paper 1) LESSON 13: SIMPLIFYING EXPONENTIAL EXPRESSIONS USING FACTORISATION 1 1 hour 10 Term Duration Date Grade Simplification of exponents, also using factorisation. Sub-topics RELATED CONCEPTS/ TERMS/VOCABULARY Factorisation by taking out the Common Factor. Simplification using exponential laws. PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Laws of exponents RESOURCES Textbooks : Mind Action Series; Answer Series and Study and Master study guide Previous question papers. ERRORS/MISCONCEPTIONS/PROBLEM AREAS Incorrect cancellation: e.g. 32𝑥 −3𝑥 .2 3𝑥 ( Learners just cancel 3𝑥 𝑎𝑛𝑑 3𝑥 ) ending up with 32𝑥 − 2 as the answer METHODOLOGY Revision of laws of exponents done in previous grades. The following examples will be done as examples: 1. 3.7 x 1 10.7 x 11 x .7 7 = 3.7 x.7 10.7 x 11 x .7 7 [Using laws of exponents] 7 x 21 10 11 x .7 7 11 = 11 7 = [Common factor] [Dividing by 7𝑥 ] 7 2. 4x 4 2x 2 22x 4 = 2x 2 2 [Change 4𝑥 to prime base] 2 2 2 2 2 2 = x x x 2x 2 [Numerator is the difference of 2 squares: so factorise] 30 3. 21026 −21024 √22044 = 21024 (22 −1) 21022 = 21024−1022 (4 − 1) = 22 (3) = 12 [HCF law used] [Application of the division law of exponents] Learners will be doing the Classwork Activity individually, with the assistance of the teacher. Homework given. 1.13 ACTIVITIES/ASSESSMENTS Classwork activity: 1.13.1 Simplify 3x 1 3x 2 a) 3x 3x 2 b) 2 x 2 2 x 3 12.2 x c) 3x 1 3x 2 8.3x 1 d) 8 x 2 x 2.16 x 1 16 x 1 Homework activity : 1.13.2 Simplify: 2n 2 22 n a) 22 n 3n.5 3n 1 b) 3n.4 5n 1 5n 1 c) 5n.10 5n 1 31 1 Term TOPIC: ALGEBRA Weighting: (30/100 marks from Paper 1) LESSON 14: EXPONENTIAL EQUATIONS 1 hour 10 Duration Grade Date Exponential Equations Sub-topics PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Laws of exponents Factorisation Solving quadratic equations RESOURCES Textbooks : Mind Action Series; Answer Series and Study and Master study guide Previous question papers METHODOLOGY Examples done on the board with learners actively involved: Example 1 5x 25 5 x 52 x2 Example 2 1 x2 8 2 12 2 x 8 x 64 Example 3 1 2 x3 4 2 x 3 2 2 x 3 2 x 1 32 Example 4 1 2 1 4 x 3x 2 0 2 1 14 4 x 3x 2 14 14 x 2 x 1 0 1 4 1 4 x 2 or x 1 4 4 14 14 4 4 x 2 or x 1 x 16 or x 1 Learners will then be given activities for classwork, as well as homework. 1.14 ACTIVITIES/ASSESSMENTS Classwork: Activity 1.14.1: 1.14.1 Solve for 𝑥: a) 5𝑥 = 125 b) 5𝑥 = 1 c) 5𝑥 = 0,04 d) 5𝑥 = 4𝑥 e) 2. (12)𝑥+3 = 32 f) 36𝑥 = 216 g) 5. 4𝑥−2 = 160 h) 4. 9𝑥+1 = 108 i) 𝑥 2 = 100 Homework: Activity 1.14.2: 1.14.2 Solve for x: a) 𝑥 2 = −100 b) 𝑥 3 = 64 c) 𝑥 3 = −64 d) 𝑥 8 = 256 1 e) 𝑥2 = 4 f) 𝑥3 = 5 g) 𝑥3 = 9 h) 1 2 1 2 1 4 x 5x 6 0 1.14.3 If 6𝑥 = 5, find the value of 18 x . 2x 33 TOPIC: ALGEBRA Weighting: (30/100 marks from Paper 1) LESSON 15: LINEAR EQUATIONS 1 hour 10 Duration Grade 1 Term Date 1. Revise the solution of linear equations Sub-topics RELATED CONCEPTS/ TERMS/VOCABULARY solving an equation/ linear equation PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Like terms/ transposing/ additive and multiplicative inverses/ factorization/ removing brackets RESOURCES Siyavula, Mind Action Series, Pinetown Document on Lesson Plans ERRORS/MISCONCEPTIONS/PROBLEM AREAS Incorrect use of signs when removing brackets and after transposing to the other side METHODOLOGY Solving an equation means determining the value(s) of a variable in an equation that will make the left hand side and the right side equal to each other. Examples: 1. 2𝑠 + 3 = 11 Solution: 2𝑠 + 3 = 11 2𝑠 + 3 − 3 = 11 − 3 [applying the additive inverse] 2𝑠 = 8 1 1 2𝑠. 2 = 8 . 2 s=4 Checking: Substituting s = 4 in 2𝑠 + 4 = 11 makes both sides equal to 11. Hence: s = 4 is the solution. 2. 𝑥+2 4 𝑥−6 1 + 3 =2 𝑥+2 𝑥−6 1 Solution: + 3 =2 4 3(x + 2) + 4(x – 6) = 6 3𝑥 + 6 + 4𝑥 − 24 = 6 7𝑥 − 24 = 0 7𝑥 − 24 + 24 = 24 7𝑥 = 24 1 1 . 7𝑥 = 24. 7 7 [multiplying through by the LCD] [removing the brackets] [applying the additive inverse] [applying the multiplicative inverse] 24 𝑥= 7 1.15 ACTIVITIES/ASSESSMENTS Classwork Activity 1.15.1 Solve the following equations: (a) 3𝑘 − 8 = 7 (b) (c) (d) 4 + 2𝑡 = −2 2+𝑥 3 1 −2=3 𝑑 + 3(𝑑 + 1) = 2(𝑑 + 8) (e) 𝑥+5 3 +𝑥 =1 (f) 3 x 2 4 x 1 24 x 7 (g) 2 x 12 2 x 32 x 3 (h) 5 2 x 8 4 4 3x 12x 34 Homework: Activity 1.15.2: Solve the following equations: (a) (b) (c) 5𝑚 − 3 = 2𝑚 + 12 4𝑥 5 𝑥 + 16 = 32 𝑥+1 + 3 = 17 2 (d) 5 1 3 4 x 2x 4 4 5 2 3 (e) 51 3 p 210 p 10 p (f) 1 3 2 m 1 m m 2 35 1 Term Sub-topics TOPIC: ALGEBRA Weighting: (30/100 marks from Paper 1) LESSON 16: QUADRATIC EQUATIONS 1 hour 10 Duration Grade Date 2. Solve Quadratic Equations (by factorisation) RELATED CONCEPTS/ TERMS/VOCABULARY Solving an equation/ writing equation in standard form/ zero –factor law PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Factorisation of polynomials/ difference of two squares/ RESOURCES Siyavula, Mind Action Series, Pinetown Document on Lesson Plans, Study & Master study guide ERRORS/MISCONCEPTIONS/PROBLEM AREAS Incorrect use of signs when removing brackets and after transposing to the other side METHODOLOGY A quadratic equation is an equation where the highest exponent of the variable is 2. To solve a quadratic equation ▫ Write the equation in standard form i.e. 𝑎𝑥 2 + 𝑏𝑥 + 𝑐 = 0 ▫ Factorise the left hand side i.e. 𝑎𝑥 2 + 𝑏𝑥 + 𝑐. ▫ Apply the zero–factor law ▫ Write down the values of the variable (solutions). Examples : Solve for x: 1. 𝑥 2 − 2𝑥 + 2 = 2 𝑥 2 − 2𝑥 + 2 − 2 = 0 𝑥 2 − 2𝑥 = 0 𝑥(𝑥 − 2) = 0 𝑥 = or 𝑥 − 2 = 0 𝑥 = 0 or 𝑥 = 2 2. [writing the equation in standard form] [factorising the left hand side] [applying the zero – factor law] [writing the solutions] 12𝑥 2 − 4𝑥 = 0 [already in standard form] 4𝑥(3𝑥 − 1) = 0 [factorising the left hand side] 4𝑥 = 0 or 3𝑥 − 1 = 0 [applying the zero – factor law] 1 𝑥 = 0 or 𝑥 = 3 [solutions] NOTE: You could also have started by first dividing both sides by the common factor and then continued to solve the equation e.g 12𝑥 2 − 4𝑥 = 0 3𝑥 2 − 𝑥 = 0 [dividing through by 4, the common factor] x(3𝑥 − 1) = 0 [factorising the left hand side] 𝑥 = 0 or 3𝑥 − 1 = 0 [applying the zero – factor law] 1 𝑥 = 0 or 𝑥 = 3 BUT never divide through by a variable that you are solving for, because you will lose one of the solutions. E.g 12𝑥 2 − 4𝑥 = 0 12𝑥 − 4 = 0 1 𝑥 = 3 !!!!!! Only one solution; the other is LOST. 36 1.16 ACTIVITIES/ASSESSMENTS Solve the following equations: Classwork Activity 1.16.1: (a) 15𝑥 2 − 5𝑥 = 0 (b) 3𝑥 2 − 9𝑥 = – 6 (c) 𝑥 2 − 10𝑥 + 25 = 0 (d) (𝑥 − 2)2 = 0 (e) (𝑥 − 3)(𝑥 − 2) = 12 (𝑥 − 2)2 = 16 (f) Homework Activity 1.16.2: (a) 𝑥 2 − 4 = 0 (b) 2𝑥 2 + 14𝑥 − 16 = 0 (c) 6(1 − 𝑥)2 = 𝑥 (d) −𝑥 2 + 4𝑥 = 4𝑥 2 − 14𝑥 + 9 37 TOPIC: ALGEBRA Weighting: (30/100 marks from Paper 1) LESSON 17: QUADRATIC EQUATIONS (CONTINUED) 1 hour 10 Duration Date Grade 1 Term 2. Solve Quadratic Equations Sub-topics RELATED CONCEPTS/ TERMS/VOCABULARY solving an equation/ writing equation in standard form/ zero –factor law/ division by zero (restrictions) PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Algebraic fractions/ finding LCD/ factorization of polynomials/ meaning of restrictions RESOURCES Siyavula, Mind Action Series, Pinetown Document on Lesson Plans, Study & Master study guide ERRORS/MISCONCEPTIONS/PROBLEM AREAS Incorrect use of signs when removing brackets and after transposing to the other side Dividing through by a variable thus losing one of the solutions or making the expression not defined if the variable is equal to zero Not checking validity of solutions METHODOLOGY Restrictions arise when the variable is in the denominator, e.g. 2 , (here 𝑥 ≠ 0 ‼); or 𝑥 3 𝑥−2 , (now 𝑥 ≠ 2 !!) You should always be on the lookout for such restrictions when working with algebraic fractions otherwise your solutions will be incorrect. Examples: 3𝑥 5 7 1. 𝑥+1 + 𝑥 = 𝑥 2 +𝑥 Solution : 3𝑥 𝑥+1 5 7 + 𝑥 = 𝑥(𝑥+1) 3𝑥 2 + 5(𝑥 + 1) = 7 [multiplying through by LCD] 3𝑥 2 + 5𝑥 + 5 = 7 [removing brackets] 3𝑥 2 + 5𝑥 − 2 = 0 [writing the equation in standard form] (3𝑥 − 1)(𝑥 + 2) = 0 [factorising the left-hand side] (3𝑥 − 1) = 0 or (𝑥 + 2) = 0 [applying the zero-factor law] 1 𝑥 = 3 or 𝑥 = −2 [solutions] 63 4 7 And if x 2 the LHS = RHS = . 2 1 Checking solutions: if 𝑥 = , the LHS = RHS = 3 38 2. x x 3 2x x 1 x 1 𝑥−3 2𝑥 Solution: 𝑥 − 𝑥−1 = 𝑥−1, restriction: 𝑥 ≠ 1 𝑥(𝑥 − 1) − (𝑥 − 3) = 2𝑥 [multipying through by LCD] 2 𝑥 − 𝑥 − 𝑥 + 3 = 2𝑥 [removing brackets] 2 𝑥 − 4𝑥 + 3 = 0 [adding like terms and writing equation in standard form] (𝑥 − 1)(𝑥 − 3) = 0 𝑥 = 1 𝑜r 𝑥 = 3 But 𝑥 = 1 is not a solution as stated in the restriction above‼! So 𝑥 = 3 is the ONLY solution. 1.17 ACTIVITIES/ASSESSMENTS Classwork: Activity 1.17.1: Solve the following equations: 2 x 2 5 x 12 0 (a) (b) (c) (d) 1 2 2𝑥 2 = 3 𝑥 2 + 3𝑥 + 14 3 2𝑥 𝑥−3 5 𝑥−2 5𝑥−3 𝑥 + 9−𝑥 2 = 𝑥+3 4 3 − 𝑥 = 𝑥+6 Homework: Activity 1.17.2: Solve the following equations: (a) (b) (c) 2𝑥 2 – 2𝑥 = 12 7 2 𝑥2 1 5 − 𝑥 = 𝑥2 + 2 4 3𝑥−2 3 1 − 2𝑥−3 = 2𝑥−1 39 Term 1 TOPIC: ALGEBRA Weighting: (30/100 marks from Paper 1) LESSON 18: LITERAL EQUATIONS 1 hour 10 Duration Grade Sub-topics Date Literal equations RELATED CONCEPTS/ TERMS/VOCABULARY Literal Equations A literal equation is one that has several different letters or variables, e.g. scientific formulas. Letters are used as the coefficients and variables in a literal equations, e.g: A r 2 , the formula for the area of a circle with radius r. In this example A is called the subject of the formula. PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE How to solve linear equations. RESOURCES Gr. 10 Mathematics Answer series Gr. 10 Platinum Mathematics Gr. 10 Classroom Mathematics KZN 2021 Gr. 10 Step Ahead Document ERRORS/MISCONCEPTIONS/PROBLEM AREAS Mistakes made in changing of signs when transposing terms. METHODOLOGY LESSSON INTRODUCTION Learners will be given the following introductory activity to do: 1. Solve for x: 2 x 3 7 2. Solve for y: 4 2 y 8 3. Solve for y: 3x 4 y 7 Solve for x: 2 x a b Solve for y: x 2 y t Solve for y: ax by z LESSON DEVELOPMENT Examples: 1. Make x the subject of the formula: qx mx p qx mx p x q m p p x if q m qm [take out x as common factor on the LHS] 40 2. Make r the subject of the formula: A R2 r 2 A R2 r 2 r 2 R2 r R2 A A 3. Consider the formula A P 1 ni . 3.1 3.2 Make i the subject of the formula. Hence determine the value of i if A= R 13 000, P = R10 000 and n= 3. Answer: 3.1 A P 1 ni A 1 ni P A ni 1 P A ni 1 P A 1 i 1 P n 3.2 A 1 i 1 P n 13000 1 i 1 10 000 3 i 0,1 SUMMARY: Steps for solving a literal equation: Remember that the aim is to isolate the subject of the formula. Begin by moving any terms containing the required subject of the formula to the left-hand side of the equation. Move all terms that do not contain the subject of the formula to the right-hand side. If the required subject of the formula appears in more than one term, factorise to isolate it. Divide through by the coefficient of the required subject of the formula. ACTIVITIES/ASSESSMENTS Activity 1.18.1: Make x the subject of the formula: (a) ax b c (c) (b) 3a 2b ax (d) x 2 3 2 1 x y z p m2 41 Activity 1.18.2: (a) Consider the formula v u at : (i) Make a the subject of the formula. (ii) Hence determine the value of a, if v = 75, u = 15 and t = 5. (b) Given the formula S 2rh 2r 2 : (i) Make h the subject of the formula. (ii) Hence determine the value of h if S = 1 221, and r= 10,5. (iii) The total surface area of which type of solid can be calculated using this formula? (c) Given the formula A P 1 i : (i) Make i the subject of the formula. (ii) Hence determine the value of i, if P = R 12 000, n = 6 years and A = R 24 983,42, correct to two decimal places. n Activity 1.18.3: (a) (b) 4 The volume of the a sphere is given by V r 3 : 3 (i) Make r the subject of the formula. (ii) Determine the value of r , if V = 4 188,79 cm3 (i) (ii) (c) 9 Given F C 32 which is the formula that is used to convert to convert temperatures from 5 degrees Celsius to degrees Fahrenheit. (i) Derive the formula that will convert degrees Fahrenheit to degrees Celsius, i.e. make C the subject of the formula. (ii) (d) n a l . 2 Write a as the subject of the formula. Evaluate a if s =38,5 ; n = 11 and l = 11,5. Given the formula: s The temperature in Montreal in Canada is 25 F . Convert this temperature to degrees Celsius. Make f the subject of the formula in: 1 1 1 . u v f x 1 i 1 , make x the subject of the formula. Given F i V Given r : h (i) Make h the subject of the formula. (ii) Solve for h , if V= 400 and r = 5 (correct to two decimal places). n (e) (f) (g) Solve for x in mx n nx m mn. n m 42 Term TOPIC: ALGEBRA Weighting: (30/100 marks from Paper 1) LESSON 19: LINEAR INEQUALITIES 2 hours 10 Duration Grade 1 Date Linear Inequalities Sub-topics RELATED CONCEPTS/ TERMS/VOCABULARY 1. Linear inequalities are like equations; except that the equal sign is replaced by an inequality sign. Practical examples: The speed limit on a highway. Minimum payments of credit cards. 2. Infinity refers to the absence of a limit, the absence of an end. METHODOLOGY LESSON INTRODUCTION ACTIVITY Recap the solving of linear equations: Solve for x: 1. 3x 4 8 2. 4 x 3 x 3 x 2 3. 2 x 7 5 x 1 LESSON DEVELOPMENT Linear equation: Linear inequality: If x 7 13 , then x 6 . If x 7 13 , then x 6 or x 6 ; . This means that any value of x that is greater than 6 will make the inequality true. Illustrated on a number line: 0 6 If x 7 13 , then x 6 or x ; 6 This means that any value of x that is less than or equal to 6 will make the inequality true. Illustrated on a number line: 0 6 Take note Round brackets: endpoint is excluded Square brackets: endpoint is included 43 THE LOGIC OF SOLVING THE LINEAR INEQUALITIES Solving linear inequalities is very similar to solving linear equations. Consider the following: Given the inequality 4 8 , on both sides….. Action: Result Is the result a true statement, or not? 59 Add 1 True 3 7 Subtract 1 True 8 16 Multiply by 2 True Divide by 2 True 24 8 16 Multiply by – 2 False; it should be: 8 16 Divide by – 2 False; it should be: 2 4 2 4 – 16 –8 8 16 0 It can clearly be seen from the number line that e.g. 8 16 (8 is to the left of 16), but 8 16 ( 8 is to the right of 16 ). Conclusion: The inequality signs changes direction when an inequality is multiplied or divided through by a negative number. EXAMPLES Solve for x, and write the solution in interval notation. Also illustrate your solution on a number line. 1. 6 x 3 x 2 3 6 x 6x – 3(x+2 ) >3+6x 6x – 3x – 6 >3+6x – 3x > 9 x < –3 OR [simplify] [divide by –3] [solution] (– ∞ ; –3) –3 2. x x 1 2 5 10 2x – 10 ≤ 20 – x 3x ≤ 30 x ≤ 10 OR (– ∞ , 10 ] [multiply by 10 throughout the inequality] [divide by 3] [solution] 0 3. 10 2 x 3 10 1 x 7 –1 4. 0 5 1 3 x 10 6 3x 9 2 x 3 3 x 2 OR –3 0 7 3 ; 2 0 2 44 ACTIVITIES/ASSESSMENTS Activity 1.19.1 (Day 1 ) Classwork: Solve for x , where x R , giving the solution in interval notation. Also illustrate your solution on a number line. 1. 2. 3. 4. x + 6 > 10 1 – 2x > x – 2 5( 2x – 1) 35 5x 3 x 1 2 3x 5. 2 3 2 x 2 2 x 7 Homework: Solve for x , where x R , giving the solution in interval notation. Also illustrate your solution on a number line. 6. 2 x 3 5 x 76 x3 5 8 2 3 x 3 7 x 3 3 8. 2 4 4 x 2x 1 9. x2 2 3 3x 1 3x 3 19 10. 4 8 8 7. ACTIVITY 1.19.2 ( Day 2 ) Classwork: Solve for x , where x R , giving the solution in interval notation. Also illustrate your solution on a number line. 2 2 x 4 2 2 x 3 10 5 2 x 3 11 12 3 3x 6 x 5. 0 1 3 3 1. 2. 3. 4. Homework: Solve for the unknown, giving the solution in interval notation. Also illustrate your solution on a number line. m 6. 1 2 4 3 3x 2 7. 4 8 2 1 x 1 1 8. 2 6 12 1 x 1 1 9. 1 4 12 3 6 10. ax x 1 a 45 1 Term Sub-topics TOPIC: ALGEBRA Weighting: (30/100 marks from Paper 1) LESSON 20: SIMULTANEOUS LINEAR EQUATIONS 2 hours 10 Duration Date Grade Solving Simultaneous Linear Equations, using the Substitution method. RELATED CONCEPTS/ TERMS/VOCABULARY Equation is a statement that the values of two mathematical expressions are equal. Root is a solution to an equation usually expressed as a number, a single term or an expression. Simultaneous means together or at the same time. Simultaneous equations are two or more equations with two or more unknowns to be solved. PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Algebraic expressions Linear equations Solving simultaneous equations using elimination method RESOURCES Answer Series Grade 10 Study & Master Study guide Grade 10 Siyavula Grade 10 Classroom Mathematics Grade 10 ERRORS/MISCONCEPTIONS/PROBLEM AREAS Use of the six operation signs when solving equations Transposing a term from one side of an equal sign to the other side Removal of brackets Simplification of algebraic terms METHODOLOGY SUBSTITUTION METHOD Use the simplest of the two given equations to express one of the variables in term of the other. Substitute the above in the remaining equation and the equation will remain with one unknown. Solve the new equation using the rules of solving equations. Substitute the solution from above in the simpler equation to determine the value of the remaining variable. Check the validity of your solutions. Example 1 Solve simultaneously using the substitution method: 𝑦 = 2𝑥 – 3 and 𝑥 + 𝑦 = 3: Solution: 𝑦 = 2𝑥 – 3 … … . (1) 𝑥 + 𝑦 = 3 … … . … … . . (2) Substitute (1) in (2): Substitute x 2 in (2): 2 y 3 𝑥 + 2𝑥 – 3 = 3 3𝑥 = 6 y 1 𝑥 = 2 Checking the validity of the solution: From (1): RHS 22 3 1 LHS From (2): LHS 2 1 3 RHS 46 Example 2: Solve for x and y using the substitution method: 𝑥 + 2𝑦 = 11 and 2𝑥 – 3𝑦 = −6. Solution: 𝑥 + 2𝑦 = 11 … … . (1) 2𝑥 – 3𝑦 = −6 … … (2) From (1): x 11 2 y ………..(3) Substitute (3) in (2): 2(11 − 2𝑦) – 3𝑦 = −6 22 – 4𝑦 – 3𝑦 = −6 22 – 7𝑦 = − 6 7𝑦 = 28 𝑦 = 4 Substitute y = 4 in (3): 𝑥 = 11 – 2 × 4 = 3 Checking the validity of the solution: From (1): LHS 3 24 11 RHS From (2): LHS 23 34 6 RHS Example 3: 𝑥 𝑦 Solve for x and y using the substitution method: 3 + 2 = 1 and 𝑥 + 2𝑦 = 1. x y 1 …………………..(1) 3 2 𝑥 + 2𝑦 = 1 … … … … … … … . . (2) From (2): x 1 2 y ……………..(3) Substitute (3) in (1): 1 2 y y 1 ………………(4) 3 2 21 2 y 3 y 6 (4) 6 : 2 4 y 3y 6 y 4 Subst. y 4 in (2): x 2 4 1 x9 Checking the validity of the solution: 9 4 3 2 1 RHS From (1): LHS 3 2 From (2): LHS 9 2 4 1 RHS 47 1.20 ACTIVITIES/ASSESSMENTS Activity 1.20.1 Classwork (a) Solve the following simultaneously using the substitution method: (i) 𝑝 + 2𝑞 = 1 and 3𝑝 – 𝑞 = 10 (ii) 2𝑥 = 3𝑦 – 4 and 𝑦 = 3 – 𝑥 (b) Solve simultaneously using the elimination method 𝑦 𝑥 1 1 1 + 1 = and 𝑥 + = 𝑦 2 5 4 2 3 Activity 1.20.2 Homework (a) Solve the following simultaneously using substitution method: (i) 𝑦 = 2𝑥 + 1 and 𝑥 + 2𝑦 + 3 = 0 (ii) 5 = 𝑥 + 𝑦 and 𝑥 = 𝑦 – 2 (iii) 3𝑥 − 4𝑦 = −4 and − 2𝑥 – 𝑦 = 10 (b) Solve the following simultaneously using any method: 𝑥 𝑦 𝑦 𝑥 (i) 4 = 2 – 1 and 4 + 2 = 1 (ii) (iii) 𝑥+1 4 𝑥+𝑦 2 = 2𝑦 – 8 and = 7 − 2𝑥−𝑦 3 𝑥+𝑦 2 and − 𝑥−𝑦 𝑥−𝑦 4 3 − = 1 𝑥+𝑦 3 1 + 42 = 0 48 Term Sub-topics 1 TOPIC 1: ALGEBRA Weighting: (30/100 marks from Paper 1) LESSON 21: SIMULTANEOUS EQUATIONS (CONTINUED) 1 hour 10 Duration Date Grade Solving Simultaneous Linear Equations, using the Elimination method. RELATED CONCEPTS/ TERMS/VOCABULARY An equation is a statement that the values of two mathematical expressions are equal A root is a solution to an equation, usually expressed as a number, a single term or an expression Simultaneous means together or at the same time. Simultaneous equations are two or more equations with two or more unknowns to be solved. PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Algebraic expressions Linear equations Removal of brackets RESOURCES Siyavula Grade 10 Classroom Mathematics Grade 10 Study & Master Mathematics Study Guide Grade 10 Answer Series Grade 10 ERRORS/MISCONCEPTIONS/PROBLEM AREAS Use of the six operation signs when solving equations Transposing a term from one side of an equal sign to the other side without changing its sign. METHODOLOGY When solving for two unknown variables, two variables are required as well as two or more equations and these equations are called simultaneous equations. The solutions are the values of the unknown variables which satisfy both equations simultaneously and they are called the roots of the equations Simultaneous equations can be solve algebraically using elimination method or algebraic method Simultaneous equations can be solved graphically Simultaneous equations are used to determine the point of intersection of graphs. Elimination method: Step 1: Multiply each equation by a suitable number so that the two equations have the same leading coefficient. Step 2: Subtract or add the two equations in order to eliminate one of the unknowns Step 3: Solve for the unknown variable that is left using the rules of solving equations Step 4: Substitute the value of the unknown solved in step 3 in one of the simple equations given to determine the value of the remaining variable. Step 5: Check the validity of your solutions. 49 Example 1: Solve for x and y 𝑥 + 𝑦 = 10 … … (1) x – y = 2 …… (2) Solution using the Elimination method: (1)+ (2): 2x = 12 Divide both sides by 2: x=6 Substitute x = 6 in (1): 6 + y = 10 𝑦 = 10 − 6 y=4 Checking the validity of the solution: From (1): 6 + 4 = 10 From (2): 6–4=2 Example 2: Solve for a and b 2a +3b = 8 …… (1) 3a + 4b = 11…… (2) Solution using the Elimination method (1) × 3: 6a + 9b = 24 ……. (3) (2) × 2: 6a + 8b = 22 …….. (4) (3) – (4): b=2 Substitute b = 2 in (1): 2a 32 8 a 1 Checking the validity of the solution: From (1): 2+6=8 From (2): 3 + 8 = 11 Example 3: Solve for x and y: 𝑥 𝑦 = 3 ………….(1) 5 𝑥 4 𝑦 = 2 – 1……….(2) Solution using the Elimination method: (2) × 4: x = 2y – 4 ………(3) 5𝑦 (1) × 5: 𝑥 = (3) – (4): 0 = 2𝑦 − 3 – 4….(5) 3 … … … … (4) 5𝑦 0 = 6𝑦 – 5𝑦 – 12 y = 12 Subst. y = 12 in (3): 𝑥 = 2 × 12 − 4 = 20 Checking the validity of the solution: 20 12 4 and 4 From (1): 5 3 20 12 5 and 1 5 From (2): 4 2 (5) × 3: 50 1.21 ACTIVITIES/ASSESSMENTS 1.21.1 Classwork Solve the following simultaneously, using the substitution method: (a) 𝑥 + 7𝑦 = 49 and 𝑥 + 3𝑦 = 9 (b) 𝑥 + 𝑦 = 8 and 3𝑥 + 2𝑦 = 21 (c) 3𝑥 – 14𝑦 = 0 and 𝑥 – 4𝑦 + 1 = 0 1.21.2 Homework (a) Solve the following simultaneously, using the substitution method: (i) 𝑥 + 𝑦 = 1 and 𝑦 – 2𝑥 = 3 (ii) 2𝑦 = 𝑥 + 1 and 𝑥 + 𝑦 – 2 = 0 (iii) 𝑦 – 3𝑥 = 2 and 2𝑦 − 5𝑥 – 10 = 0 𝑥 𝑦 𝑦 𝑥 (iv) = 2 – 1 and 4 + 2 = 1 2 (b) Solve the following simultaneously, using any method 𝑎 𝑎 𝑏 (i) 2 + b = 4 and 4 – 4 = 1 1 1 (ii) 𝑥 + 𝑦 = 3 and 1 1 – = 11 𝑥 𝑦 51 Term Sub-topics 1 TOPIC 1: ALGEBRA Weighting: (30/100 marks from Paper 1) LESSON 22: WORD PROBLEMS 1 hour 10 Duration Grade Date Word problems, leading to equations. RELATED CONCEPTS/ TERMS/VOCABULARY More means add Less means subtract Double means multiply by two PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Linear equations Simultaneous equations Distance = speed × time Changing the subject of the formula RESOURCES Siyavula Grade 10 Classroom Mathematics Grade 10 Study & Master Mathematics Study Guide Grade 10 Answer Series Grade 10 ERRORS/MISCONCEPTIONS/PROBLEM AREAS The use of correct units when forming equations Substitution Understanding of the language used Answering the question at the end METHODOLOGY Steps for approaching word problems: Read very carefully and make sure that you understand the given information Drawing your own diagram or table can be very helpful Decide what you have to determine and use a variable (usually x and/or y) to represent it Hint: if more than one unknown is present, let the smallest value be x Write the other unknown in terms of x You may also choose to name the other unknown to be y Use the remaining information to set-up the equation/s Answer the question that was asked and discard a solution that is that is nor realistic Check your answers Useful information[S1] Area of rectangle = length × breadth Perimeter of a rectangle = 2(length + breadth) Profit = selling price – cost price Distance = speed × time If I am x years now; then: five years from now, I will be (x + 5) years old. 52 EXAMPLE 1: SPEED/DISTANCE/TIME A boy covered 31 km in 4 hours, partly by cycling at 14 km/h and partly walking at 4 km/h. How far has he walked? Solution: Let the distance he walked be x km The distance he cycled will then be (31 – x) km Speed for cycling = 14 km/h Speed for walking = 4 km/h distance 31 x hours Time cycling speed 14 Time walking distance x hours speed 4 Time cycling + Time walking = 4hrs 31 x x 4 14 4 231 x 7 x 428 62 2 x 7 x 112 5 x 50 x 10 He has walked 10 km. [multiply through by LCD = 28] EXAMPLE 2: COST A hotel charges R200 less per day for a child than for an adult. A family of 2 adults and 3 children stay there for 6 days. The bill at the end is R11 400. How much does the hotel charge per day for a child? Solution: Let the charge per adult be Rx. The charge per child will then be R(x – 200) 12 x 18 x 200 11 400 Total cost: 12x 18x 3600 11400 30x 15 000 x 500 The charge per adult per day is R500 and the charge per child per day is R500 – R200 = R300. 1.22 ACTIVITIES/ASSESSMENTS 1.22.1 Classwork: (a) Two cars are travelling in the same direction and the distance between them is 0,1 km. The car in front is travelling at 120 km/h and the car at the back at 125 km/h. After how long will the car at the back overtake the car in front? Give your answer in minutes. (b) A shop sells bicycles and tricycles. In total there are 7 cycles and 19 wheels. How many bicycles and how many tricycles are there? 1.22.2 Homework: (a) A fruit shake costs R2 more than a chocolate milk shake. If 3 fruit shakes and 5 chocolate milk shakes cost R78, determine the individual prices. (b) A train travels 120 km at a constant speed. If it had travelled 6 km/h faster, it would have taken one hour less to complete the journey. Calculate its actual speed. (c) 600 tickets have been sold for the school concert. The tickets for adults cost R30 each and the tickets for learners R15 each. The total amount of money from the ticket sales was R13 200. How many learner tickets have been sold? 53 Term Sub-topics 1 TOPIC 1: ALGEBRA Weighting: (30/100 marks from Paper 1) LESSON 23: WORD PROBLEMS (CONTINUED) 1 hour 10 Duration Date Grade Word Problems RELATED CONCEPTS/ TERMS/VOCABULARY More means add Less means subtract Double means multiply by two Constant or uniform speed Factorisation PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Linear equations Quadratic equations Simultaneous equations Distance = speed x time Changing the subject of the formula RESOURCES Siyavula Grade 10 Mathematics Classroom Mathematics Grade 10 Study & Master Mathematics Study Guide Grade 10 Answer Series Mathematics Grade 10 ERRORS/MISCONCEPTIONS/PROBLEM AREAS The use of correct units when forming equations Substitution Understanding of the language used Factorisation METHODOLOGY Continuation from the previous lesson on Word problems. More examples will be discussed with learners, and they will be given more activities to do on this topic. EXAMPLE 1: The combined ages of two people is 72 years. In 10 years’ time the first one will be 3 times as old as the second one was 6 years ago. How old are the two people now? Solution: The first person is now x years old. The second person is now (72 –x) year old. In 10 years’ time the first person will be( x + 10) years old. 6 years ago the second person was ( 66 –x) years old. Ten years from now: x + 10 = 3(66 – x) x 10 198 3 x 4 x 188 x 47 At present the first person is 47 years old. The second person is (72 – 47) = 25 years old. 54 EXAMPLE 2: A two-digit number is such that if the digits are interchanged, the resulting number is one less than double the original number. Three times the sum of the digits is 7 less than the original number. Determine the original number. Solution: Let the number be (10y + x). 10 x y 210 y x 1 8x 19 y 1 ……………..…(1) 3 x y 10 y x 7 2 x 7 y 7 ………….…….(2) (2) 4: 8x 28 y 28 ………………(3) (1) – (3): 9 y 27 y 3 2 x 73 7 Substitute y 3 in (2): x7 The number is 37. EXAMPLE 3: The breadth of a rectangle is 3 cm less than the length and the area is 10 cm². Determine the dimensions of the rectangle. Solution: Let the length be x cm and the breadth will then be (x – 3) cm. Area = length × breadth x x 3 10 x 2 3 x 10 x 2 3 x 10 0 x 5x 3 0 x 5 or x 3 Since length cannot have a negative value, x 5 . The length is 5 cm and the breadth is 2 cm. 1.23 ACTIVITIES/ASSESSMENTS 1.23.1 Classwork: (a) John is 21 years older than his son, Andile. The sum of their ages is 37. How old is Andile? (b) The sum of two consecutive odd numbers is 20. Determine the values of the two odd numbers. (c) The product of two consecutive negative integers is 1 122. Determine the values of the two integers. 1.23.2 HOMEWORK: (a) Tapelo is currently four times as old as his daughter, Lindy. Six years from now, Tapelo will be three times as old as Lindy. Calculate Lindy’s current age. (b) A grocer mixes 10 kg of fudge with 20 kg of nougat that costs R11,00/kg more. He sells the mixture at R62,50/kg. If he makes a profit of R275,00, what is the price of 1kg of fudge? (c) The length of a rectangle is twice the breadth and its area is 128 cm². Calculate the length and the breadth of the rectangle. (d) The tens digit of a number is double the units digit. If 27 is subtracted from the number, the digits of the number interchange in the new number. What was the original number? 55 TOPIC 2: EUCLIDEAN GEOMETRY Weighting: (30/100 marks from Paper 2) LESSON 1: REVISION OF LINES AND ANGLES FROM GR. 9 EUCLIDEAN GEOMETRY 1 1 hour 10 Term Duration Date Grade Sub-topics Revision of lines and angles RELATED CONCEPTS/ TERMS/VOCABULARY Parallel lines, intersect, vertex PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Types of angles RESOURCES Grade 10 Mind Action Series Grade 10 Siyavula Maths ERRORS/MISCONCEPTIONS/PROBLEM AREAS Assuming that lines are parallel METHODOLOGY An angle is formed where two straight lines meet at a point, also known as a vertex. Angles are labelled with a caret on a letter, for example, Â. Angles can also be labelled according to the line segments that make up the angle, for example 𝐶Â𝐵 𝑜𝑟 𝐵Â𝐶. The "∠" symbol is a short method of writing angle in geometry and is often used in phrases such as “sum of ∠𝑠 in ∆". Angles are measured in degrees which is denoted by °, a small circle raised above the text, similar to an exponent. Types of Angles 1. Adjacent angles on a straight line are supplementary. Supplementary angles add up to 180° ˆ B ˆ 180 . B̂1 and B̂2 share a vertex and a common side. Hence B 1 2 2. If two lines intersect, vertically opposite angles are equal.Two lines intersect if they cross each other at a point. Vertically opposite angles are angles opposite each other when two lines intersect.They share a vertex and are equal. Ê1 Ê 3 and Ê 2 Ê 4 56 3. The angles around a point add up to 360° (A revolution). Bˆ1 Bˆ 2 Bˆ3 Bˆ 4 3600 PARALLEL LINES Parallel lines are always the same distance apart (equidistant) and they are denoted by arrow symbols as shown below. 𝐶𝐷 ∥ 𝐴𝐵. EF is a transversal line. A transversal line intersects two or more parallel lines. Below are the properties of the angles formed by the above intersecting lines. 1. Corresponding Angles Corresponding angles lie either both above or both below the lines and on the same sideof the transversal. If the lines are parallel, the corresponding angles will be equal. 2. Alternate Angles Alternate angles lie on opposite sides of the transversal and between the lines. If the lines are parallel, the alternate angles will be equal. 3. Co-interior Angles Co-interior angles lie on the same side of the transversal between the lines.If the lines are parallel, the co-interior angles are supplementary If two lines are intersected by a transversal such that corresponding angles are equal; or alternateangles are equal; or co-interior angles are supplementary, then the two lines are parallel. 57 2.1 ACTIVITIES Exercise 1: Mind Action Series (Pg. 165) Activity 2.1.1: 1. In ∆ABC, EF∥BC. BA is produced to D. a) Calculate, with reasons, the value of 𝑎 and hence show that AE = AF. b) Calculate, with reasons, the value of 𝑏, 𝑐, 𝑑, 𝑎𝑛𝑑 𝑒. 2. In the diagram below, CD∥EF, DÊF = 28°, B̂ = 48° and BD̂E 160 . Prove that AB∥CD. 3. In the diagram below, PU∥ 𝑄𝑇, T̂ 42 , RQ̂S 82 , PQ̂T y , UPT = x and QPT = x + 40°. a) Prove that PT∥QS b) Calculate y 58 TOPIC: EUCLIDEAN GEOMETRY Weighting: (30/100 marks from Paper 2) LESSON 2: REVISION OF TRIANGLES FROM GR. 9 EUCLIDEAN GEOMETRY 1 1 hour 10 Term Duration Date Grade Sub-topics Revise Triangles: Classification, Congruency and Similarity RELATED CONCEPTS/ TERMS/VOCABULARY PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Types of angles RESOURCES Grade 10 Mind Action Series Grade 10 Siyavula Maths ERRORS/MISCONCEPTIONS/PROBLEM AREAS Using congruency conditions without understanding METHODOLOGY PROPERTIES OF TRIANGLES A triangle is a three-sided polygon. Triangles can be classified according to sides and also be classified according to angles. 1. TYPES OF TRIANGLES according to sides a) Scalene Triangle: b) Isosceles Triangle: Two sides are equal. Angles opposite equal sides are equal. c) Equilateral Triangle All three sides are equal. All three interior angles are equal 59 2. TYPES OF TRIANGLES according to angles a) Acute-angled Triangle All 3 interior angles are less than 90° b) Obtuse-angled Triangle One interior angle is greater than 90° The other two are acute c) Right-angled Triangle One interior angle is equal to 90° The other two are acute From Pythagoras Theorem 2 AB AC2 +BC2 AC2 =AB2 BC2 In triangle ABC, BC is produced to D.  B̂ Ĉ 2 180 (Sum of ∠𝑠 of a ∆) Ĉ1  B̂ (ext. ∠ of ∆) 3. CONGRUENT TRIANGLES – 4 Conditions a) If three sides of a triangle are equal in length to the corresponding sides of another triangle, then the two triangles are congruent. Side, Side, Side (S, S, S) b) If two sides and the included angle of a triangle are equal to the corresponding two sides and included angle of another triangle, then the two triangles are congruent. Side, Angle, Side (S, A, S) c) If one side and two angles of a triangle are equal to the corresponding one side and two angles of another triangle, then the two triangles are congruent. Angle, Angle, Side (A, A, S) d) If the hypotenuse and one side of a rightangled triangle are equal to the hypotenuse and the corresponding side of another right-angled triangle, then the two triangles are congruent. 90°, Hypotenuse, Side (R, H, S). We use ≡ to indicate that triangles are congruent. NOTE: The order of letters when labelling congruent triangles is very important. 60 4. SIMILAR TRIANGLES Two triangles are similar if one triangle is a scaled version of the other. This means that their corresponding angles are equal in measure and the ratio of their corresponding sides are in proportion. The two triangles have the same shape, but different scales. Congruent triangles are similar triangles, but not all similar triangles are congruent. We use /// to indicate that two triangles are similar. a) If all three pairs of corresponding angles of two triangles are equal, then the triangles are similar. Angle, Angle, Angle (A, A, A) b) If all three pairs of corresponding sides of two triangles are in proportion, then the triangles are similar. NOTE: The order of letters for similar triangles is very important. Always label similar triangles in corresponding order. 5. THEOREM OF PYTHAGORAS AB 2 AC 2 BC 2 if Ĉ 90 2.2 ACTIVITIES: Activity 2.2.1: Exercise 1: Mind Action Series (Pg. 166) 1. AB∥DE and DC = CB a) Prove that AC = CE and AB = DE 2. Prove that C1 90 using congruency. 3. Show that the following triangles are similar. 61 4. If ∆𝐴𝐵𝐶///∆𝐷𝐸𝐶, calculate x and y. Activity 2.2.2: TEST 1: LINES, ANGLES AND TRIANGLES MARKS: 25 DURATION: 30 Min QUESTION 1 In the diagram below, AB and DC are two parallel lines cut by two transversal lines at X, Y and Z respectively. A X 𝑥 Z 60 D B Y C 𝑥 − 20° 1.1.1 Determine giving reasons, the value of 𝑥 in the diagram: (6) 1.1.2 Name one pair of co-interior angles (1) 1.1.3 Name one pair of alternate angles (1) 1.1.4 Complete: If two parallel lines are cut by a transversal, then the co-interior angles are …………….. (1) 1.1.5 Complete: The size of angle XYD = ………………. (2) Reason ..................... 62 QUESTION 2 In the diagram below, AD = CD and PQ∥RS. AR and FC are straight lines. RS and FC intersect at E. PQ also intersects FC at B. 2.1 2.2 Determine the sizes of the following angles, giving appropriate reasons: 2.1.1 D̂1 (2) 2.1.2 B̂1 (2) 2.1.3  2 (2) ˆ ˆ Show that REF=B 3 (3) [9] 63 Term Sub-topics 1 TOPIC 2: EUCLIDEAN GEOMETRY Weighting: (30/100 marks from Paper 2) LESSON 3: PROPERTIES OF QUADRILATERALS (1) 1 hour 10 Duration Date Grade Properties of Quadrilaterals (sides, angles and diagonals) RELATED CONCEPTS/ TERMS/VOCABULARY Polygon, Straight line, diagonals, bisect, intersect, adjacent PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Parallel lines, interior angles RESOURCES Grade 10 Mind Action Series Grade 10 Siyavula Maths ERRORS/MISCONCEPTIONS/PROBLEM AREAS Treating parallelogram as a rectangle or as a rhombus. METHODOLOGY A quadrilateral is a closed shape (polygon) consisting of four straight line segments.A polygon is a two-dimensional figure with three or more straight sides. The interior angles of a quadrilateral add up to 360°. 1. PARALLELOGRAM A parallelogram is a quadrilateral with both pairs of opposite sides parallel. 2. RECTANGLE A rectangle is a parallelogram that has all four angles equal to 90°. 3. RHOMBUS A rhombus is a parallelogram with all four sides of equal length. 4. SQUARE A square is a rhombus with all four interior angles equal to 90°. A square has all the properties of a rhombus. OR A square is a rectangle with all four sides equal in length. 5. TRAPEZIUM A trapezium is a quadrilateral with at least one pair of opposite sides parallel. NOTE: A trapezium is sometimes called a trapezoid. 6. KITE A kite is a quadrilateral with two pairs of adjacent sides equal. 64 PROPERTIES OF QUADRILATERALS QUATRILATERAL PARALLELOGRAM RECTANGLE RHOMBUS RECTANGLE TRAPEZIUM PROPERTIES • Both pairs of opposite sides are parallel. • Both pairs of opposite sides are equal in length. • Both pairs of opposite angles are equal. • Both diagonals bisect each other. • Both pairs of opposite sides are parallel. • Both pairs of opposite sides are of equal length. • Both pairs of opposite angles are equal. • Both diagonals bisect each other. • Diagonals are equal in length. • All interior angles are equal to 90° • Both pairs of opposite sides are parallel. • Both pairs of opposite sides are equal in length. • Both pairs of opposite angles are equal. • Both diagonals bisect each other. • All sides are equal in length. • The diagonals bisect each other at 90° • The diagonals bisect both pairs of opposite angles. • Both pairs of opposite sides are parallel. • Both pairs of opposite sides are equal in length. • Both pairs of opposite angles are equal. • Both diagonals bisect each other. • All sides are equal in length. • The diagonals bisect each other at 90° • The diagonals bisect both pairs of opposite angles. • All interior angles equal 90°. • Diagonals are equal in length. • One pair of opposite side are parallel. • The diagonals of a trapezium intersect but don’t bisect each other. • Diagonals lie between parallel lines and therefore, the alternate angles are equal. 65 KITE • Diagonal between equal sides bisects the other diagonal. • One pair of opposite angles are equal (the angles between unequal sides). • Diagonal between equal sides bisects the interior angles and is an axis of symmetry. • Diagonals intersect at 90° ACTIVITIES Activity 2.3.1: 1. The following are properties of some quadrilaterals. a) Having a pair of parallel sides. b) Having two pairs of parallel sides. c) Having four right angles. d) Having four equal sides. e) Having equal diagonals. In the table below, mark a “” in the box if the quadrilateral has the property referred to in a) to e) above: PROPERTIES QUADRILATERALS a) b) c) d) e) Kite Trapezium Parallelogram Rectangle Square Rhombus 2. Referring to the figure below, use the names of the quadrilaterals to complete the sentences. 66 Term 1 TOPIC 2: EUCLIDEAN GEOMETRY Weighting: (30/100 marks from Paper 2) LESSON 4: PROPERTIES OF QUADRILATERALS (2) 1 hour 10 Duration Date Grade Sub-topics Properties of Quadrilaterals (sides, angles and diagonals) RELATED CONCEPTS/ TERMS/VOCABULARY Parallel, interior angles, bisect PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Properties of quadrilaterals, naming quadrilaterals, Naming triangles RESOURCES Grade 10 Mind Action Series Grade 10 Siyavula Maths ERRORS/MISCONCEPTIONS/PROBLEM AREAS Difference between parallelogram and rhombus METHODOLOGY EXAMPLES: 1. DELM is a parallelogram. a) Calculate the value of 𝑥 and hence the sizes of the interior angles. b) If DE = 2DM and ML = 10 cm, determine the length of the other sides of DELM. SOLUTION: 2 x x 180 a) 3x 180 x 60 Ê M̂ 60 D̂ 120 L̂ 120 b) DE = 10 cm DM = 5 cm EL = 5 cm [co-int ∠𝑠; DM∥EL] [opp ∠𝑠 of parm equal] [opp ∠𝑠 of parm equal] [opp sides of parm] [DE = 2DM] [opp sides of a parm] 2. ABCD is a parallelogram. BH bisects AB̂C and HC bisects BĈD . AB̂C 60 . F̂ 120 . BH∥GC and BG∥HC. AD is produced to E such that AB = DE = 30 cm. BC is produced to F. Prove that a) BGCH is a rectangle. b) DCFE is a rhombus. 67 SOLUTION: a) BCGH is a parallelogram AB̂C 60 B̂1 B̂2 30 BĈD 120 Ĉ1 Ĉ 2 60 Ĥ 2 90 BGCH is a rectangle b) [both pairs opp. sides are parallel] [given] [BH bisects AB̂C ] [co-int ∠s ; AB∥DC] [HC bisects BĈD ] [sum of ∠𝑠 𝑜𝑓 ∆] [BGCH is a parm with an interior ∠ = 90°] F =120° Ĉ1 Ĉ 2 120 F̂ Ĉ1 Ĉ 2 DC∥EF AD∥BC ADE and BCE are straight lines DE∥CF DCFE is a parallelogram DC = AB = 30 cm DC = DE = 30 cm DCEF is a rhombus ACTIVITIES Activity 2.4.1: 1. PQRS is a rhombus with S2 35 . [corresponding angels are equal] [opp. sides of parallelogram ABCD] [given] [both pairs opp sides are ∥ [opp sides of a parm are equal] [DCEF is a parm with adjacent sides equal] Calculate the sizes of all the interior angles 2. ABCD is a square. AÊB 55 Calculate F1 3. In rectangle ABCD, AB = 3x and BC = 4x Determine the length of AC and BD in terms of x. 4. ABCD is a trapezium with AD||BC. AB = AD and BD = BC. Ĉ 80 Determine the unknown angles. 68 5. ABCD is a kite. The diagonals intersect at E. BD = 30 cm, AD =7 cm and DC = 25 cm. Determine: a) AE b) AC c) B̂1 if Â1 20 . Term Sub-topics 1 TOPIC 2: EUCLIDEAN GEOMETRY Weighting: (30/100 marks from Paper 2) LESSON 5: PROPERTIES OF QUADRILATERALS (3) 1 hour 10 Duration Date Grade Properties of Quadrilaterals (sides, angles and diagonals) RELATED CONCEPTS/ TERMS/VOCABULARY Triangle, quadrilaterals, parallel PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Types of quadrilaterals and Properties of quadrilaterals RESOURCES Grade 10 Mind Action Series Grade 10 Siyavula Maths ERRORS/MISCONCEPTIONS/PROBLEM AREAS Properties of a kite, stating reasons METHODOLOGY Example: In trapezium ABCD, AD||BC with  D̂ 70 and EC = DC. Prove that ABCE is a parallelogram. Solution: Ê 2 70 AB || EC ABCE is a parallelogram [∠s opp = sides] [corresponding s are equal] [both pairs opposite sides are equal] 69 ACTIVITIES Activity 2.5.1: 1. Determine the sizes of the interior angles of parallelogram ABCD. 2. In ∆ABC,  80 and Ĉ 35 Calculate the interior angles of parallelogram MENB. 3. In parallelogram ABCD, AB = BE = DE. D̂1 x and Â1 28 . Calculate x. 4. AD = BD = BC. Ĉ 75 and AD̂B 30 . Prove that ABCD is a parallelogram. 70 Term TOPIC 2: EUCLIDEAN GEOMETRY Weighting: (30/100 marks from Paper 2) LESSON 6: PROPERTIES OF QUADRILATERALS (4) 1 hour 10 Duration Date Grade 1 Sub-topics The opposite Sides and Angles of a parallelogram are equal RELATED CONCEPTS/ TERMS/VOCABULARY Properties of parallelogram, congruent triangles PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Diagonals, Parallel RESOURCES Grade 10 Mind Action Series Grade 10 Siyavula Maths ERRORS/MISCONCEPTIONS/PROBLEM AREAS Naming angles as sides METHODOLOGY The proofs of the following theorems are examinable in Gr. 10 Euclidean Geometry: 1. The opposite sides and angles of a parallelogram are equal. 2. The diagonals of a parallelogram bisect each other. 3. The diagonals of a rectangle are equal. 4. The diagonals of a rhombus bisect each other at right angles and bisect the angles of the rhombus. As an example the proof of the first of these theorems is given below: Prove that the opposite sides and angles of a parallelogram are equal. PROOF: Given: Parallelogram ABCD. R.T.P.: AB = CD and AD = BC 2 1 BÂD BĈD and B̂ D̂ Construction: Draw diagonal AC. Proof: In ABC and CDA : 1.  2 Ĉ1 [alt. ' s; AB || CD] 2. Â1 Ĉ 2 [alt. ' s; AD || BC] 2 1 3. AC AC [common] ABC CDA [ ;; s ] AB CD and BC AD and B̂ D̂ [ ' s ] Also: Â1  2 Ĉ1 Ĉ 2 [  2 Ĉ1 ; Â1 Ĉ 2 ] BÂD BĈD 71 ACTIVITIES Activity 2.6.1 1. KLMN is a parallelogram Calculate the size of the interior angles 2. In parallelogram ABCD, AB = 50 cm and E is a point on AD such that AB = AE and CD = DE. Determine: a) DE b) the perimeter of ABCD. 3. ABCD is a parallelogram. AM bisects  . AB = AM. Ĉ 120 . Calculate the size of the interior angles. 72 Term Sub-topics 1 TOPIC 2: EUCLIDEAN GEOMETRY Weighting: (30/100 marks from Paper 2) LESSON 7: PROPERTIES OF QUADRILATERALS (5) 1 hour 10 Duration Date Grade The diagonals of a parallelogram bisect each other RELATED CONCEPTS/ TERMS/VOCABULARY Diagonals PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Properties of a parallelogram, congruent triangles RESOURCES Grade 10 Mind Action Series Grade 10 Siyavula Maths ERRORS/MISCONCEPTIONS/PROBLEM AREAS Choosing triangles to prove congruency. METHODOLOGY The proofs of the following theorems are examinable in Gr. 10 Euclidean Geometry: 1. The opposite sides and angles of a parallelogram are equal. 2. The diagonals of a parallelogram bisect each other. 3. The diagonals of a rectangle are equal. 4. The diagonals of a rhombus bisect each other at right angles and bisect the angles of the rhombus. As a further example the proof of the second of these theorems is given below: Prove that the diagonals of a parallelogram bisect each other: Given: Parallelogram ABCD with diagonals AC and BC intersecting in E. R.T.P.: AE = EC and BE = ED Proof: In ABE and CDE : 1.  2 Ĉ1 [alt. ’s; AB || CD] 2. B̂1 D̂ 2 [alt. ’s; AB || CD] 3. AB = CD [opp. sides of parm] [AAS] ABE CDE AE = EC and BE = ED [ s ] 73 EXAMPLE: Diagonals AC and BD of parallelogram ABCD intersect at M. AP = QC and AC =600 mm,AB = 500 mm and AP =150 mm. Prove that PBQD is a parallelogram SOLUTION: AM = MC [diagonals of a parm] But AC = 600 mm [given] AM = MC = 300 mm AP =QC =150 mm [given] PM = MQ =150 mm Also, BM = MD [diagonals of parm] ∴ PM = MQ and BM =MD ∴ PBQD is a parallelogram [diagonal of quad bisect] ACTIVITIES Activity 2.7.1: 1. In the diagram, BCDF, EDCF and ABCF are parallelograms. BC = 4 units and CD = 6 units. Prove that ABDE is a parallelogram. 2. Parallelograms ABCD and ABDE are given with DF = DB. Prove that BCFE is a parallelogram. 3. ABCD is a parallelogram with AE = FC. Prove that BEDF is a parallelogram. 74 1 Term TOPIC 2: EUCLIDEAN GEOMETRY Weighting: (30/100 marks from Paper 2) LESSON 8: PROPERTIES OF QUADRILATERALS (6) 1 hour 10 Duration Date Grade If one pair of opposite sides of a quadrilateral are equal and parallel, then the quadrilateral is a parallelogram. RELATED CONCEPTS/ TERMS/VOCABULARY Diagonal, parallel Sub-topics PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Congruent triangles RESOURCES Grade 10 Mind Action Series Grade 10 Siyavula Maths ERRORS/MISCONCEPTIONS/PROBLEM AREAS Prove congruency and reasons for congruency METHODOLOGY TAKE NOTE: Learners need to be able to apply the theorem below, but the proof of the theorem is not examinable. It is given here as enrichment. Theorem: If one pair of opposite sides of a quadrilateral are equal and parallel, then the quadrilateral is a parallelogram Required to prove: ABCD is a parallelogram: Construction: Draw diagonal AC. Proof: In ABC and CDA : (a) Ĉ 2 Â1 [alt. s ; AD || BC ] (b) AC = AC [common] (c) BC = AD [given] ABC CDA [SAS]  2 Ĉ1 [ s ] AB || CD [alt. s are equal] ABCD is a parallelogram [both pairs opp. sides are ||] 75 ACTIVITIES Activity 2.8.1: 1. In parallelogram ABCD, AB =AD and Ĉ 100 . Calculate the sizes of all the interior angles. 2. ∆ABD and ∆BCD are two isosceles triangles. Ĉ 75 and AD̂B 30 . Prove that ABCD is a parallelogram. 3. In quadrilateral LMNP, Ê1 62 , P̂1 68 , FP = FN and LE = LM. Prove that: a) LP||MN b) LMNP is a parallelogram 4. In quadrilateral ABCD, AB = 5 cm, BC = 10 cm, FD = 3 cm, BE = FD and AE = FC. AE ⊥ BC and CF ⊥ AD. Prove that ABCD is a parallelogram. 76 Term Sub-topics TOPIC 2: EUCLIDEAN GEOMETRY Weighting: (30/100 marks from Paper 2) LESSON 9: MIDPOINT THEOREM 2 hours Duration Grade Midpoint Theorem 1 10 Date RELATED CONCEPTS/ TERMS/VOCABULARY Midpoint PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Parallel lines, types of angles, properties of parallelogram RESOURCES Grade 10 Mind Action Series Grade 10 Siyavula Maths ERRORS/MISCONCEPTIONS/PROBLEM AREAS Assuming that any point on a line is its midpoint METHODOLOGY The midpoint is the centre of a line segment (it bisects the line segment). MIDPOINT THEOREM: CONVERSE OF MIDPOINT THEOREM: A D B If AD = DB and AE = EC, 1 then DE∥BC and DE= BC 2 A E D C B E C If AD = BD and DE∥BC 1 then AE = EC and DE= BC 2 77 ACTIVITIES Activity 2.9.1 INVESTIGATING THE MIDPOINT THEOREM Use a ruler and determine midpoint S of side PQ and midpoint T of side PR of triangle PQR. Indicate on the sketch that PS = SQ and PT = TR. Draw ST. 1. Measure each of the following angles, using a protractor: 1.1 Q̂ .......... ... degrees 1.3 PŜT .......... ... degrees 1.2 R̂ .......... ... degrees 1.4 PT̂S .......... ... degrees 2. What do you notice concerning your answers in question 1? (4) ………………………………………………………………………………………………(2) 3. Using your answer to question 2, what can you conclude concerning ST and QR? ………………………………………………………………………………………………(1) 4. Give a reason for your answer in question 3. ………………………………………………………………………………………………(1) 5. Measure the lengths of the following sides: 5.1 ST = ………………. mm 6. What do you notice concerning the lengths of ST and QR? 5.2 QR = ………………. mm (2) ………………………………………………………………………………………………(1) 5. Hence, make a conjecture regarding the line joining the midpoints of two sides of any triangle: ……………………………………………………………………………………………………… ….…………………………………………………………………………………………………… ………………………………………………………………………………………………(2) 78 In this part all answers have to be justified, using accurate measurements of distances and/or angles. Given: GHJ with K on GH, and L on GJ. 1. Are K and L the midpoints of GH and GJ respectively? …………………………………………………………………………………..…………… (2) 2. Is KL || HJ? ……………………………………………………………………………………………….. (3) 3. Is HJ = 2KL? …………………………………………………………………………………………………(1) Activity 2.9.2: Given: AD = 5 cm and MC = 6 cm. 1. A Calculate, with reasons: 1.1 The length of BM 1.2 The length of DP 1.3 The length of DE D P M B C E 79 2. In ∆ACD, AB = BC, GE =15 cm, AF = FE = ED. Calculate the length of CE. 3. M, N and T are the midpoints of AB, BC and AC of ABC . Â=60 and B̂=80 . A 60 ° Calculate the interior angles of MNT . T M 80 B ° N C Activity 2.9.3 1. In ∆ABC, AD = DB and AE = EC. DE is produced to F. DB||FC and BC = 32 mm. a) Prove that DBCF is a parallelogram. b) Calculate the length of DE. 2. In ∆ABC, AE = EB and EF||BC. In ∆ ACD, FG||CD. Prove that AG = GD. 3. In ∆DEF, DS = SE, EU = EF and ST||EF. Prove that SEUT is a parallelogram. 80 TOPIC 2: EUCLIDEAN GEOMETRY Weighting: (30/100 marks from Paper 2) LESSON 10: CONSOLIDATION OF GR. 10 EUCLIDEAN GEOMETRY 1 2 hours 10 Term Duration Grade Date Sub-topics Consolidation ACTIVITIES/ASSESSMENTS Activity 2.10.1 1. Study the diagram below and calculate the unknown angles w, x, y and z. A F z x Give reasons for your statements. y 53 C B 2. DBE NOV. 2015 GRADE 10 In the diagram below, PQRS is a parallelogram having diagonals PR and QS intersecting in M. B is a point on PQ such that SBA and RQA are straight lines and SB = BA. SA cuts PR in C and PA is drawn. 2.1 Prove that SP = QA. 2.2 Prove that SPAQ is a parallelogram Prove that AR = 4MB. 2.3 3. M C P Q B A A B AÔD O Calculate the length of AO. 36,87 3.3 R Write down the size of the following angles: 3.1.1 CD̂O 3.1.2 3.2 E S In the diagram, ABCD is a rhombus having diagonals AC and BD intersecting ˆ in O. ADO=36,87 and DO = 8 cm. 3.1 w 74 D If E is a point on AB such that OE | | AD, calculate the length of OE. D 8 cm C 81 4. ABC is right angled at B. F and G are midpoints of AC and BC respectively. H is the midpoint of AG. E lies on AB such that FHE is a straight line. 4.1 Prove that E is the midpoint of AB. 4.2 If EH = 3,5cm and the area of AEH=9,5cm2 , calculate the length of AB. 4.3 Hence, calculate the area of ABC . 82 TOPIC 3: TRIGONOMETRY Weighting: (40/100 marks from Paper 2) LESSON 1: DEFINITIONS OF TRIGONOMETRIC RATIOS 1 1 hour 10 Term Duration Grade Date 1. Define the trigonometric ratios sin , cos and tan using rightSub-topic(s) angled triangles. RELATED CONCEPTS/ Pythagoras theorem, Sum of the angles of a triangle, Hypotenuse, Adjacent TERMS/VOCABULARY Side/ Angles, Opposite side, Reciprocals, Period, Amplitude, maximum value, minimum value; decreasing function and increasing PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Different types of Triangles, Linear equations, types of different angles, RESOURCES Calculators, Text Books NOTES : BASELINE ASSESSMENT : Ratios and Theorem Of Pythagoras Example 1 Given Calculate the following ratios and write them in simplest form. 1.1 1.2 1.3 𝐴𝐵 𝐷𝐸 𝐵𝐶 𝐸𝐹 𝐴𝐶 𝐷𝐹 = = = = = = 83 Example 2 Example 3 What is the length of the hypotenuse in the following triangles State which side of the following triangles Is the Hypotenuse Example 4 The three side length of two right- angled triangles are listed below. For each triangle state the length of the hypotenuse Opposite to A B C Adjacent to Hypotenuse - The side opposite the 90° angle (longest side) Opposite - The side opposite the angle C Adjacent - The remaining side next to C 84 Definition of trig ratios: The ratio opp opp is called the sine of the angle θ and can be written as sin . hyp hyp The ratio adj adj is called the cosine of the angle θ and can be written as cos . hyp hyp The ratio opp opp is called the tangent of the angle θ and can be written as tan . adj adj cos b. c. d. sin e. cos f. tan tan A Opposite to Example: Consider the following diagram and answer the questions that follow. State the following: a. sin B C Adjacent to 3.1 ACTIVITIES/ASSESSMENT Activity 3.1.1: 3.1.1 Determine the following trig ratios 85 3.1.2 State the following 3.1.3 State the following 86 TOPIC 3: TRIGONOMETRY Weighting: (40/100 marks from Paper 2) LESSON 2: THE RECIPROCAL TRIGONOMETRIC RATIOS 1 1 hour 10 Term Duration Grade Date Define the reciprocals trigonometric ratios cosec , sec and cot using Sub-topic(s) right-angled triangles. (These three reciprocals should be examined in grade 10 only.) Pythagoras theorem, Sum of the angles in a triangle, Hypotenuse, Adjacent Side/ RELATED CONCEPTS/ Angles, Opposite side, Reciprocals, Period, Amplitude, maximum value, TERMS/VOCABULARY minimum value; decreasing function and increasing. PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Different types of Triangles, Linear equations, types of different angles. RESOURCES Calculators, Text Books NOTES : Example : 1 2 3 2 has a reciprocal of ; and has a reciprocal of 2 1 2 3 cosec = 1 sin 𝜃 = 𝐻𝑦𝑝𝑜𝑡𝑒𝑛𝑢𝑠𝑒 𝑂𝑝𝑝𝑜𝑠𝑖𝑡𝑒 Leaners to complete: sin R = cosec R = cos R = sec R = tan R = cot R = 3.2 ACTIVITIES/ASSESSMENT Activity 3.2.1 Refer to the diagram alongside to answer the following questions: State the value of each of the following a) b) c) d) e) f) sec A cot A cosec A cot C cosec C sec C 87 TOPIC 3: TRIGONOMETRY Weighting: (40/100 marks from Paper 2) LESSON 3: SPECIAL ANGLE VALUES 1 1 hour 10 Term Duration Grade Date Derive values of the trigonometric ratios for the special angles (without Sub-topic(s) using a calculator), 0 ; 30 ; 45 ; 60 ; 90 . Pythagoras theorem, Sum of the angles in a triangle, Hypotenuse, Adjacent RELATED CONCEPTS/ Side/ Angles, Opposite side, Reciprocals. TERMS/VOCABULARY PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Different types of Triangles. Linear equations. Types of different angles. RESOURCES Grade 10 textbooks Ruler Protractor Pencil NOTES : Special Angles Begin by constructing an isosceles right – angled triangle: (angles of 90 ; 45; 45) sin 30 = sin 60 = cos 30 = cos 60 = tan 30 = tan 60 = 88 3.3 ACTIVITIES/ASSESSMENT Activity 3.3.1 Determine the value of each of the following without using a calculator: 1. sin 2 30 cos 2 30 2. sin 2 30 cos 2 60 3. sin30.tan 45.cos 45 4. sin 45 cos 45 5. cos30.tan 60 cos ec 45.sin 60 6. sin 30.sec 45 1 2 sin 60 2 2 Activity 3.3.2 Evaluate the following trigonometric ratios with the use of calculators. Round off all answers to two decimal places. 1. cos10 2. sin312 3. sin35 sin 75 4. sin 43 cos 43 5. cos 24 24 2 2 89 TOPIC 3: TRIGONOMETRY Weighting: (40/100 marks from Paper 2) LESSON 4: TRIGONOMETRIC EQUATIONS 1 1 hour 10 Term Duration Grade Date Solve simple trigonometric equations for angles between 00 and 900. Sub – topic(s) RELATED CONCEPTS/ Minimum value, maximum value. TERMS/VOCABULARY PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Linear equations. Types of different angles. RESOURCES Calculators. Text Books. NOTES: Solving of simple trigonometric equations for angles between 0 0 and 900 . Example 1: Consider cos 0,5 Steps: Use a calculator, shift button and enter cos ( cos 1 ). cos 1 0,5 600 Examples: 1 2 sin 1 0 1 sin 2 1 sin 1 2 300 3. sin 3 0,157 3 sin 1 0,157 3 9,0328...... 3,010 2 sin 3 0 3 sin 2 3 sin 1 2 A calculator will show Math Error. This means the equation has no solution. This is simple because the ratios of cos and sin have a maximum value of 1, hence they cannot be solved for values greater than 1. 2. 4. cos x 600 0,5 x 60 cos0,5 0 x 600 600 x 600 600 x 00 90 3.4 ACTIVITIES/ASSESSMENT Activity 3.4.1 Solve the following equations and round off your answers to 2 decimal places: tan 0,357 1. 2cos 3 2. 3. 2sin x 1 2 5. 7. 9. 4. 2 tan 10 3 5 1 cos 3x 0,12 3 6. 3cos 2 12 2 1 3 sin x cos 33 2 8. sec x 10 5, 649 tan 1 2,32 0,3 10. 4 cos 2 1 91 TOPIC 3: TRIGONOMETRY Weighting: (40/100 marks from Paper 2) LESSON 5: EXTEND THE DEFINITIONS OF TRIGONOMETRIC RATIOS TO 0 360 (1) 1 1 hour 10 Term Duration Grade Date Sub-topic(s) Extend definitions of sin 𝜃, cos 𝜃 and tan 𝜃, for 0° ≤ 𝜃 ≤ 360° RELATED CONCEPTS/ TERMS/ VOCABULARY Cartesian plane, anticlockwise, radius PRIOR KNOWLEDGE/ BACKGROUND KNOWLEDGE Trigonometric ratios, intervals RESOURCES Mind Action Series, Maths handbook and Study Guide, Study & Master, Siyavula ERRORS/MISCONCEPTIONS/PROBLEM AREAS Choosing the correct quadrant in the Cartesian plane METHODOLOGY Angles in a Cartesian plane Positive angles are measured in an anti-clockwise direction from the positive x-axis Example 1: Determine in which quadrants the following angles lie: 92 Trigonometric Ratios in the Cartesian Plane The CAST Diagram The CAST diagram summarizes where trigonometric ratios are positive. Example 2 Determine in which quadrant does the terminal arm of the angle lie if: a. sin 0 and cos >0 d. tan 0 and b. sin 0 and cos 0 e. sin 0 and 90; 270 c. tan 0 and f. cos 0 and 0 180 cos 0 cos 0 3.5 ACTIVITIES/ASSESSMENT Activity 3.5.1 Give the quadrant in which the radius will lie for each of the following: 5 and 0;180 13 (b) tan sin 12 and 0;270 13 (d) sec cot 4 and 0;180 3 (a) cos (c) (e) 4 and 180;360 3 5 and 0;180 3 93 TOPIC 3: TRIGONOMETRY Weighting: (40/100 marks from Paper 2) LESSON 6: EXTEND DEFINITIONS OF TRIGONOMETRIC RATIOS TO 0 360 (2) 1 1 hour 10 Term Duration Grade Date Using diagrams to determine the numerical values of ratios for angles from Sub-topic(s) 0 to 360 Pythagoras theorem, Sum of the angles in a triangle, Hypotenuse, Adjacent RELATED CONCEPTS/ Side/ Angles, Opposite side, Reciprocals, Cartesian Plane, etc. TERMS/VOCABULARY PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Different types of Triangles. Linear equations. Types of different angles. Quadrants RESOURCES Grade 10 textbooks Ruler Protractor Pencil METHODOLOGY 94 Examples 1. If 3sin 1 and 90; 270 calculate without the use of a calculator, and with the aid of a diagram, the value of cos sin : sin 2. Consider the diagram below. Point T 2;3 is a point on the Cartesian plane such that is the angle of inclination of OT. y 1 r 3 sin is negative in 3rd quadrant Calculate the following, without the use of a calculator: a. tanβ 3 b. c. sin cos x2 y2 r 2 x 2 1 32 2 x2 9 1 x 8 y x r r 1 8 3 3 a. 1 8 3 b. 13sinβ.cosβ r 13 tan 3 2 sin 2 cos 2 2 3 2 13 13 9 4 13 13 1 c. 2 3 2 13sin cos 13 6 13 13 ACTIVITIES/ASSESSMENT Activity 3.6.1 95 2.1 Calculate the length of OR 2.2 State the values of the six trigonometric ratios of . 96 1 Term Sub-topic(s) TOPIC 3: TRIGONOMETRY Weighting: (40/100 marks from Paper 2) LESSON 7: TRIGONOMETRIC GRAPHS (1) 1 hour 10 Duration Grade Date Point-by-point plotting of basic trigonometric graphs defined by 𝑦 = sin 𝜃, 𝑦 = cos 𝜃 and 𝑦 = tan 𝜃 for 𝜃 ∈ [0°; 360°]. Angles on a Cartesian Plane, Special Angles, Intercepts, Turning points, Maximum/Minimum points, etc. RELATED CONCEPTS/ TERMS/ VOCABULARY PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Different types of Triangles. Linear equations. Types of different angles. Quadrants Coordinates RESOURCES Grade 10 textbooks Ruler Protractor Pencil Graph paper (if possible) METHODOLOGY : 97 ACTIVITY/ASSESSMENT Activity 3.7.1: Using point-by-point plotting, sketch the graphs of the following trigonometric functions: 𝑓(𝑥) = sin 𝑥, 𝑓(𝑥) = cos 𝑥, 𝑓(𝑥) = tan 𝑥 on different sets of axes, for θ∈[0°;360°]. 98 Term Sub-topic(s) 1 TOPIC 3: TRIGONOMETRY Weighting: (40/100 marks from Paper 2) LESSON 8: TRIGONOMETRIC GRAPHS (2) 1 hour 10 Duration Grade Date Study the effect of a and q on the graphs defined by y a sin q ; y a cos q ; and y a tan q ; for 0 ; 360 .. RELATED CONCEPTS/ Transformation, amplitude, turning point. TERMS/VOCABULARY PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Sketching trigonometric functions, intuitive understanding of the shapes of the graphs of sin, cos, tan . Minimum value and maximum value RESOURCES Calculator Textbooks METHODOLOGY: Examples: Teacher to draw the graph of y tan x . Due to the difference in characteristics between the graph of y tan x and those of y sin x and y cos x , the concept of asymptotes needs to be reintroduced. Sketching of the graph by point by point method: 99 ACTIVITIES/ASSESSMENT Activity 3.8.1 100 TOPIC 3: TRIGONOMETRY Weighting: (40/100 marks from Paper 2) LESSON 9: SOLVING 2D-PROBLEMS INVOLVING RIGHT-ANGLED TRIANGLES 1 1 hour 10 Term Duration Grade Date Sub-topic(s) Solve two-dimensional problems involving right-angled triangles. Pythagoras theorem, Sum of the angles in a triangle, Hypotenuse, Adjacent Side/ Angles, Opposite side, Reciprocals, Period, Amplitude, maximum value, minimum value; decreasing function and increasing PRIOR-KNOWLEDGE/ BACKGROUND KNOWLEDGE Different types of Triangles, Linear equations, types of different angles. RESOURCES Calculators, Text Books METHODOLOGY RELATED CONCEPTS/ TERMS/VOCABULARY Solving problems using Trigonometric ratios: Examples: 1. Finding the length of a side: In △FUN, FN=10, ∠U=90˚ and ∠N=28˚ Calculate the length of FU, rounded off to one decimal place. Solution: Let N be the point of reference (given angle) opp sin 28 hyp FU sin 28 10 FU 4, 7 units 2. Calculating an angle: Calculate the size of θ correct to one decimal place. 101 Angles of elevation and depression 1. Angle of elevation 102 Examples: 1. The angle of depression of a boat on the ocean from the top of a cliff is 55˚. The boat is 70 metres from the foot of the cliff. a. b. What is the angle of the elevation of the top of the cliff from the boat? Calculate the height of the cliff. Solutions a. The angle of elevation of the top of the cliff from the boat is 55˚. ie ∠B=55˚ b. We calculate the height of the cliff as follows: h tan 55 7 h 70 tan 55 h 100m 2. In a soccer World Cup, a player kicked the ball from a distance of 11 metres from the goalposts (4 metres high) in order to score a goal for his team. The shortest distance travelled by the ball is in a straight line. The angle formed by the pathway of the ball and the ground is represented by θ. a. Calculate the largest angle θ for the player will possibly score a goal. b. Will the player score a goal if the angle θ is 22˚? Explain. Solutions: 4m tan a. 11m tan 0.3636..... tan 1 0.3636..... b. 20 No. The ball will go above the goalpost. 103 ACTIVITIES/ASSESSMENT: Activity 3.9.1: 3. ˆ 30 , BCD ˆ 45 and BDC ˆ 90 In the diagram, AB 10cm , BAC 104 105 ANSWERS TO QUESTIONS FROM ACITIVITIES TOPIC 1: ALGEBRA LESSON 1: NUMBER SYSTEM Activity 1.1.1 5 Real; Rational; Z; N0 ; N –2 Real; Rational; Z 4,1 Real; Rational 1 2 Real; Rational 3 Real; Rational 0,7 9 Real; Rational; Z; N0 ; N 3 8 Real; Rational; Z 10 Real; Irrational 9 16 Real; Rational 8 Non-real 8 Real; Rational; Z 9 0 5 5 0 Real; Irrational 1 3 3 Real; Rational; Z; N0 Undefined Real; Rational Activity 1.1.2 2 (a) 9 3 (b) 11 2 (c) 9 71 (d) 333 5 (e) 33 49 (f) 90 106 LESSON 2: SURDS AND PRODUCTS Activity 1.2.1 (a) between 2 and 3 (b) between 8 and 9 (c) between – 4 and – 3 Activity 1.2.2 (a) 8x 2 12x (b) 5x 2 x (c) 12x3 2 x 2 16x (d) x 2 9 x 20 (e) x 2 x 20 (f) x 2 9 x 20 (g) 14x 2 19x 3 4 x 2 18xy 18 y 2 (h) 1 1 x2 x (i) 6 6 2 (j) 25x 4 (k) 16a 2 9b 2 (l) x 2 8x 16 (m) a 2 6ab 9b 2 (n) 4a 2 20ab 25b 2 (o) 12 x 2 12 xy 3 y 2 (p) 4m2 32mn 64n 2 (q) 6 x8 5x 4 y 2 6 y 4 LESSON 3: PRODUCTS (CONTINUED) Activity 1.3.1 (a) x 3 2 x 2 3x 2 (b) 6c 3 13c 2 3c 2 (c) 3x 3 7 x 2 y 4 y 3 (d) a 3 a 2b ab2 b3 (e) a 3 3a 2b 3ab2 b3 x3 y3 (f) x 3 27y 3 (g) Activity 1.3.2 34 y 2 16 y 7 (a) (b) (c) (d) (e) (f) 4 x 2 16xy 19 y 2 41m2 4mn 4n 2 2 x 4 25 y 2 1 x2 2 2 x 6 x2 1 2 x Page 107 of 120 LESSON 4: FACTORISATION: REVISION OF GR. 9 FACTORISATION Activity 1.4.1 3 x 5 (a) (b) (c) (d) (e) (f) (g) (h) (i) 4ab3 4a 3b 5 2b 4 9a k p k p 3 3 x x x x 2 x y y 1 3a 53a 5 32a b 2a b x 1x 1x 2 1 1 1 1 1 x y x y 9 2 9 2 LESSON 5: FACTORISING TRINOMIALS Activity 1.5.2 p 5 p 3 (a) p 5 p 3 (b) p 5 p 3 (c) (d) (e) (f) (g) (h) (i) (j) (k) (l) (m) (n) (o) (p) (q) (r) (s) (t) (u) (v) p 5 p 3 x 5x 2 2a 5a 2 b 5b 2 y 5 y 2 a 12 a 7 x 24 x 2 2 x 1x 3 2a 1a 3 2a 3a 5 2 y 52 y 1 3a 22a 3 4 x 33x 2 4 x 32 x 5 11 y 12 y 1 3 x 1 x a 52 2 p 12 3a 5b2 Page 108 of 120 LESSON 6: FACTORISATION BY GROUPING IN PAIRS Activity 1.6.1 m n x y (a) p q m 1 x 4 y 1 3a 3x 2 y 2b 5c 3x 4c 2 x 3a a d c b 2 (b) (c) (d) (e) (f) LESSON 7: FACTORISATION: SUM AND DIFFERENCE OF CUBES Activity 1.7.1 (a) x 1 x 2 x 1 (b) (c) (d) 1 2 y 1 2 y 4 y 2 a 3ba 2 3ab 9b 2 4 x 516x 2 20x 25 (e) 2x 2 y 2 x 2 2 xy 2 4 y 4 (d) 4b a b 2 (f) 5a b a 2 ab b 2 a 6 a 3b 3 b 6 Activity 1.7.2 (a) x 4 x 3 (b) 5a 4 a 4 (c) 4 x 3 y 3 x 7 y (e) (f) (g) (h) (i) 2 x 10 x 2 x 100 2 10 y 100 y y y 1y 2 1 4 p 72 x y ax 3b 3 3 x x 2 2 2 (k) 4 x x x y x 2 xy y 2 x y x 2 xy y 2 (l) 4 9 x 25 (j) 2 Page 109 of 120 LESSON 8: SIMPLIFICATION OF ALGEBRAIC FRACTIONS Activity 1.8.1 (a) 2x2 1 2x 1 (b) x2 4a 2 6 a 9 (c) 3a 3 2 x 1 (d) x 3x 4 (e) 2x 2 k 3 (f) 2 3 (g) x y3 LESSON 9: ADDING AND SUBTRACTING ALGEBRAIC FRACTIONS Activity 1.9.1 1 (a) 6 x2 y2 (b) xy (c) (d) (e) (f) (g) (h) x 3 2 x 2 3x 4 x3 4a 2 15b 2 12ab 1 2a 32a 1 6 3a a 2 2 a 4 2a a 2 1 ab 3xy x y x y x 2 xy y 2 Page 110 of 120 LESSON 10: EXPONENTS Activity 1.10.1: Classwork (a) 27 (b) 1 (c) 5 (d) 1 16x 6 y 4 16 (f) 25 (g) 6 Activity 1.10.2: Homework 3 (a) 5 27 (b) 4 125 (c) 3 1 (d) 9 1 (e) 2 (e) LESSON 11: EXPONENTS Activity 1.11.1: Classwork 8 (a) 3x3 16 (b) 3 1 (c) 625 Activity 1.11.2: Homework (a) 32n1.2n 1 (b) 4 (c) 2 x7 Page 111 of 120 LESSON 12: EXPONENTS Activity 1.12.1: Classwork (a) 3 (b) 5 (c) 2 (d) 3 (e) 2a (f) 3y Activity 1.12.2: Homework (a) 2x 2 2 (b) x5 m (c) 5 x2 (d) 7 1 (e) 3 (f) 1 LESSON 13: EXPONENTS Activity 1.13.1: Classwork 6 (a) 10 1 (b) 1 (c) 2 31 (d) 16 Activity 1.13.2: Homework (a) 3 1 (b) 2 26 (c) 25 Page 112 of 120 LESSON 14: EXPONENTS Activity 1.14.1: Classwork (a) 3 (b) 0 (c) 2 (d) 0 (e) 7 3 (f) 2 9 (g) 2 1 (h) 2 10; 10 (i) Activity 1.14.2: Homework (a) no solution (b) 4 (c) 4 (d) 2 (e) 16 (f) 125 (g) 27 (h) 81; 16 Activity 1.14.3: Homework 25 Page 113 of 120 LESSON 15: LINEAR EQUATIONS Activity 1.15.1 (a) 5 3 (b) 1 8 (c) 2 1 6 (d) 2 1 (e) 2 3 (f) 5 (g) 2 1 (h) 2 Activity 1.15.2 (a) 5 (b) 20 (c) 20 (d) 1 5 (e) 2 (f) LESSON 16: QUADRATIC EQUATIONS Activity 1.16.1 1 0; (a) 3 (b) 1;2 (c) 5 (d) 2 1; 6 (e) 2;6 (f) Activity 1.16.2 2; 2 (a) 8 ;1 (b) 2 3 ; (c) 3 2 3 ;3 (d) 5 Page 114 of 120 LESSON 17: QUADRATIC EQUATIONS (CONTINUED) Activity 1.17.1 3 ;4 (a) 2 11 ;4 (b) 5 3 ; 1 is rejected (c) 2 ;12 (d) Activity 1.17.2 2;3 (a) 6 2; (b) 5 1 0; (c) 4 LESSON 18: LITERAL EQUATIONS Activity 1.18.1 cb (a) x a 2b (b) x 3 a (c) x 2m 2 2 p (d) 3 yz x 2z y Activity 1.18.2 vu (a) (i) a t (ii) a 12 S 2r 2 (b) (i) h 2r (ii) 8,01 (iii) a closed cylinder A (i) i n 1 (c) P (ii) 0,13 Page 115 of 120 Activity 1.18.3 (a) (b) (c) (d) (e) (f) 3V 4 (ii) 10,00 2s nl (i) a n 9 (ii) 2 5 (i) C F 17,78 9 (ii) 3,89 C uv f uv Fi x 1 i n 1 V (i) h 2 r (i) r 3 (ii) 5,09 (g) x mn mn LESSON 19: INEQUALITIES Activity 1.19.1 1. 4 ; 2. ; 1 3. 4 ; 4. 5 ; 5. 1 ; 6. ; 10 7. 3 ; 8. ; 9 9. 2 ; 24 9 ; Activity 1.19.2 1. 1 ; 3 2. 7 ; 5 3. 1 ; 7 4. 1 ; 5 5. 3 ; 6 10. Page 116 of 120 Activity 1.19.3 6. 9 ; 6 7. 2 ; 6 8. 3 2 ; 2 9. 10. 1 ; 10 ; 1 LESSON 20: SIMULTANEOUS EQUATIONS Activity 1.20.1 (a)(i) p 3 ; q 1 (ii) x 1; y 2 (b) x 10; y 6 1.20.2 Homework Activity 1.20.2 (a)(i) x 1; y 1 (ii) 3 7 x ;y 2 2 (iii) x 4 ; y 2 (b)(i) 4 12 x ;y 5 5 (ii) x 9 ; y 3 (iii) x 5; y 7 LESSON 21: SIMULTANEOUS EQUATIONS Activity 1.21.1 (a) x 21; y 10 (b) x 5; y 3 (c) 3 x 7; y 2 Activity 1.21.2 2 5 x ;y (a)(i) 3 3 (ii x 1; y 1 (iii) x 6; y 20 2 8 x ;y (iv) 3 3 16 4 (b)(i) x ; y 3 3 1 1 x ;y (ii) 7 4 Page 117 of 120 LESSON 22: WORD PROBLEMS Activity 1.22.1 (a) Time taken is 0,02 hours = 1,2 minutes (b) Number of bicycles is 2 and the number of tricycles is 5 Activity 1.22.2 (a) Cost of individual chocolate milk shake is R9,00 and for fruit shake is R11,00 (b) The actual speed is 24km/h (c) 320 learner tickets were sold LESSON 23: WORD PROBLEMS (CONTINUED) Activity 1.23.1 (a) Andile’s age is 8 years (b) The consecutive odd numbers are 9 and 11 (c) The negative consecutive integers are – 34 and – 33 Activity 1.23.2 (a) Lindy’s present age is 12 years (b) The price of 1 kg of fudge is R46,00 (c) The breadth is 8 cm and the length is 16 cm (d) The original number is 63 Page 118 of 120 TOPIC 3: TRIGONOMETRY LESSON 1 3.1.1 1 3.1.3 cos A sin C sin α = 𝑞 b) cos α = 𝑞 c) tan 𝛼 = 𝑟 d) sin 𝜃 = 𝑞 e) cos 𝜃 = 𝑞 f) tan 𝜃 = 𝑝 LESSON 2 3.2.1 a) sec A = 3 b) cot A = c) cosec A = 4 d) cot C = e) cosec C = f) sec C = 4 c b c b c tan A a 2. sin Z cos Z tan Z sin Y cos Y tan Y 120 5 745 65 5 745 0,88 0, 48 120 1,85 65 65 5 745 120 5 745 0, 48 0,88 65 0,54 120 3.1.2 a) b) c) d) e) f) LESSON 4 3.4.1 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. c a b cos C a b tan C c b sin B a c cos B a c tan B b sin C 19,65 30 x 30 35 x 22,97 6 x 33,99 x 69,8 44,89 41, 41 𝑝 a) 𝑟 𝑝 𝑟 𝑝 𝑟 5 3 4 5 4 3 5 3 5 LESSON 3 3.3.1 1 1 2 1 2 3. 1 2 2 4. .5. 1 6. 2 2 3 9 2 3.3.2 1. 2. 3. 4. 5. LESSON 5 3.5.1 (a) (b) (c) (d) (e) 0,985 0,743 1,54 1 0,038 quadrant 1 quadrant 3 quadrant 3 quadrant 2 quadrant 2 Page 119 of 120 LESSON 6 3.6.1 1.1 1.2 29 5 1.3 29 2 29 1.4 5 2 2.1 3.1 3.2 13 3.3 3.4 4.1 4.2 4.3 4.4 y 6 LESSON 9 3.9.1 1.1 1.2 2.1 2.2 3.1 3.2 4.1 4.2 4.3 16,35 units 14,72 units 94,65 units 86,78 units 71,57 18, 43 5,76 units 37,51 18,91 units 3 5 4 cos 5 3 tan 4 24 sin 25 sin 25 24 24 tan 7 cos ec 1 Page 120 of 120