Slide 1 / 127 Polynomials Slide 2 / 127 Table of Contents · · · · · · · · Factors and GCF Factoring out GCF's Factoring Polynomial w/ a=1 Factoring Using Special Patterns Factoring Trinomial a#1 Factoring 4 Term Polynomials Mixed Factoring Solving Equations by Factoring Slide 3 / 127 Factors and Greatest Common Factors Return to Table of Contents Factors of 10 Factors Unique to 10 Factors of 15 Factors Unique to 15 Factors 10 and 15 have in common Number Bank 1 11 2 12 3 13 4 5 6 7 8 9 10 14 15 Slide 4 / 127 16 17 18 19 20 What is the greatest common factor (GCF) of 10 and 15? Factors of 12 Factors Unique to 12 Factors of 18 Factors Unique to 18 Factors 12 and 18 have in common Number Bank 1 11 2 12 3 13 4 5 6 7 8 9 10 14 15 Slide 5 / 127 16 17 18 19 20 What is the greatest common factor (GCF) of 12 and 18? Slide 6 / 127 1 What is the GCF of 12 and 15? Slide 7 / 127 2 What is the GCF of 24 and 48? 3 What is the GCF of 72 and 54? 4 What is the GCF of 70 and 99? Slide 8 / 127 Slide 9 / 127 Slide 10 / 127 5 What is the GCF of 28, 56 and 42? Slide 11 / 127 Variables also have a GCF. The GCF of variables is the variable(s) that is in each term raised to the lowest exponent given. Example: Find the GCF and and and 6 and What is the GCF of A B C D and and and ? Slide 12 / 127 Slide 13 / 127 Slide 14 / 127 Slide 15 / 127 Slide 16 / 127 Factoring Using the Distributive Property Return to Table of Contents The first step in factoring is to determine its greatest monomial factor. If there is a greatest monomial factor other than 1, use the distributive property to rewrite the given polynomial as the product of this greatest monomial factor and a polynomial. Example 1 a) Slide 17 / 127 Factor each polynomial. 6x4 - 15x3 + 3x2 Find the GCF GCF: 3x2 Reduce each term of the polynomial dividing by the GCF 3x2 (2x2 - 5x + 1) The first step in factoring is to determine its greatest monomial factor. If there is a greatest monomial factor other than 1, use the distributive property to rewrite the given polynomial as the product of this greatest monomial factor and a polynomial. Example 1 Factor each polynomial. b) 4m3n - 7m2n2 Find the GCF GCF: m2n Reduce each term of the polynomial dividing by the GCF m2n(4n - 7n) Slide 18 / 127 Sometimes the distributive property can be used to factor a polynomial that is not in simplest form but has a common binomial factor. Example 2 a) Slide 19 / 127 Factor each polynomial. y(y - 3) + 7(y - 3) Find the GCF GCF: y - 3 Reduce each term of the polynomial dividing by the GCF (y - 3)(y + 7) Sometimes the distributive property can be used to factor a polynomial that is not in simplest form but has a common binomial factor. Example 2 b) Slide 20 / 127 Factor each polynomial. Find the GCF GCF: Reduce each term of the polynomial dividing by the GCF In working with common binomial factors, look for factors that are opposites of each other. For example: (x - y) = - (y - x) because x - y = x + (-y) = -y + x = -(y - x) Slide 21 / 127 Slide 22 / 127 10 True or False: y - 7 = -1( 7 + y) True False Slide 23 / 127 11 True or False: 8 - d = -1( d + 8) True False Slide 24 / 127 12 True or False: 8c - h = -1( -8c + h) True False Slide 25 / 127 13 True or False: -a - b = -1( a + b) True False Slide 26 / 127 Slide 27 / 127 Slide 28 / 127 14 If possible, Factor A B C D Already Simplified Slide 29 / 127 15 If possible, Factor A B C D Already Simplified Slide 30 / 127 16 If possible, Factor A B C D Already Simplified Slide 31 / 127 17 If possible, Factor A B C D Already Simplified Slide 32 / 127 18 If possible, Factor A B C D Already Simplified Slide 33 / 127 19 If possible, Factor A B C D Already Simplified Slide 34 / 127 Factoring Trinomials: x2 + bx + c Return to Table of Contents Slide 35 / 127 A polynomial that can be simplified to the form ax + bx + c , where a ≠ 0, is called a quadratic polynomial. Qu a dr Lin at Co ns t er ant te m. er rm m. . ea ic t rt A quadratic polynomial in which b ≠ 0 and c ≠ 0 is called a quadratic trinomial. If only b=0 or c=0 it is called a quadratic binomial. If both b=0 and c=0 it is a quadratic monomial. Examples: Choose all of the description that apply. Cubic Quadratic Linear Constant Trinomial Binomial Monomial Slide 36 / 127 Slide 37 / 127 20 Choose all of the descriptions that apply to: A Quadratic B Linear C Constant D Trinomial E Binomial F Monomial Slide 38 / 127 Slide 39 / 127 22 Choose all of the descriptions that apply to: A Quadratic B Linear C Constant D Trinomial E Binomial F Monomial Slide 40 / 127 23 Choose all of the descriptions that apply to: A Quadratic B Linear C Constant D Trinomial E Binomial F Monomial Slide 41 / 127 Simplify. 1) (x + 2)(x + 3) = _________________________ 3) (x + 1)(x - 5) = ________________________ 2) 4) (x - 4)(x - 1) = _________________________ (x + 6)(x - 2) = ________________________ Answer Bank x2 - 5x + 4 x2 - 4x - 5 x2 + 5x + 6 x2 + 4x - 12 RECALL … What did we do?? Look for a pattern!! Slide each polynomial from the circle to the correct expression. Slide 42 / 127 Slide 43 / 127 Slide 44 / 127 Examples: Slide 45 / 127 24 The factors of 12 will have what kind of signs given the following equation? A Both positive B Both Negative C Bigger factor positive, the other negative D The bigger factor negative, the other positive Slide 46 / 127 25 The factors of 12 will have what kind of signs given the following equation? A Both positive B Both negative C Bigger factor positive, the other negative D The bigger factor negative, the other positive Slide 47 / 127 26 Factor A (x + 12)(x + 1) B (x + 6)(x + 2) C (x + 4)(x + 3) D (x - 12)(x - 1) E (x - 6)(x - 1) F (x - 4)(x - 3) Slide 48 / 127 27 Factor A (x + 12)(x + 1) B (x + 6)(x + 2) C (x + 4)(x + 3) D (x - 12)(x - 1) E (x - 6)(x - 1) F (x - 4)(x - 3) Slide 49 / 127 28 Factor A (x + 12)(x + 1) B (x + 6)(x + 2) C (x + 4)(x + 3) D (x - 12)(x - 1) E (x - 6)(x - 1) F (x - 4)(x - 3) Slide 50 / 127 29 Factor A (x + 12)(x + 1) B (x + 6)(x + 2) C (x + 4)(x + 3) D (x - 12)(x - 1) E (x - 6)(x - 1) F (x - 4)(x - 3) Slide 51 / 127 Slide 52 / 127 Slide 53 / 127 Examples Slide 54 / 127 30 The factors of -12 will have what kind of signs given the following equation? A Both positive B Both negative C Bigger factor positive, the other negative D The bigger factor negative, the other positive Slide 55 / 127 31 The factors of -12 will have what kind of signs given the following equation? A Both positive B Both negative C Bigger factor positive, the other negative D The bigger factor negative, the other positive Slide 56 / 127 32 Factor A (x + 12)(x - 1) B (x + 6)(x - 2) C (x + 4)(x - 3) D (x - 12)(x + 1) E (x - 6)(x + 1) F (x - 4)(x + 3) Slide 57 / 127 33 Factor A (x + 12)(x - 1) B (x + 6)(x - 2) C (x + 4)(x - 3) D (x - 12)(x + 1) E (x - 6)(x + 1) F (x - 4)(x + 3) Slide 58 / 127 34 Factor A (x + 12)(x - 1) B (x + 6)(x - 2) C (x + 4)(x - 3) D (x - 12)(x + 1) E (x - 6)(x + 1) F (x - 4)(x + 3) Slide 59 / 127 Slide 60 / 127 Mixed Factoring Slide 61 / 127 36 Factor the following A (x - 2)(x - 4) B (x + 2)(x + 4) C (x - 2)(x +4) D (x + 2)(x - 4) Slide 62 / 127 37 Factor the following A (x - 3)(x - 5) B (x + 3)(x + 5) C (x - 3)(x +5) D (x + 3)(x - 5) Slide 63 / 127 38 Factor the following A (x - 3)(x - 4) B (x + 3)(x + 4) C (x +2)(x +6) D (x + 1)(x+12) Slide 64 / 127 39 Factor the following A (x - 2)(x - 5) B (x + 2)(x + 5) C (x - 2)(x +5) D (x + 2)(x - 5) Slide 65 / 127 Slide 66 / 127 Slide 67 / 127 Slide 68 / 127 Factor: Factor out STEP 1 STEP 2 STEP 3 STEP 4 Slide 69 / 127 40 Factor completely: A B C D Slide 70 / 127 41 Factor completely: A B C D Slide 71 / 127 42 Factor completely: A B C D Slide 72 / 127 43 Factor completely: A B C D Slide 73 / 127 44 Factor completely: A B C D Slide 74 / 127 Factoring Special Patterns Return to Table of Contents Slide 75 / 127 When we were multiplying polynomials we had special patterns. Square of Sums Difference of Sums Product of a Sum and a Difference If we learn to recognize these squares and products we can use them to help us factor. Perfect Square Trinomials Slide 76 / 127 The Square of a Sum and the Square of a difference have products that are called Perfect Square Trinomials. How to Recognize a Perfect Square Trinomial: Recall: Observe the trinomial. The first term is a perfect square. The second term is 2 times square root of the first term times the square root of the third. The sign is plus/minus. The third term is a perfect square. Slide 77 / 127 Examples of Perfect Square Trinomials Is the trinomial a perfect square? Drag the Perfect Square Trinomials into the Box. Only Perfect Square Trinomials will remain visible. Slide 78 / 127 Slide 79 / 127 Slide 80 / 127 45 Factor A B C D Not a perfect Square Trinomial Slide 81 / 127 46 Factor A B C D Not a perfect Square Trinomial Slide 82 / 127 47 Factor A B C D Not a perfect Square Trinomial Slide 83 / 127 Slide 84 / 127 Examples of Difference of Squares Slide 85 / 127 Slide 86 / 127 Slide 87 / 127 48 Factor A B C D Not a Difference of Squares Slide 88 / 127 50 Factor A B C D Not a Difference of Squares Slide 89 / 127 51 Factor A B C D Not a Difference of Squares Slide 90 / 127 52 Factor using Difference of Squares: A B C D Not a Difference of Squares Slide 91 / 127 Slide 92 / 127 Factoring Trinomials: ax2 + bx + c Return to Table of Contents How to factor a trinomial of the form ax² + bx + c. Example: Factor 2d² + 15d + 18 Find the product of a and c : 2 ∙ 18 = 36 Now find two integers whose product is 36 and whose sum is equal to “b” or 15. Factors of 36 Sum = 15? 1 + 36 = 37 1, 36 2 + 18 = 20 2, 18 3 + 12 = 15 3, 12 Now substitute 12 + 3 into the equation for 15. 2d² + (12 + 3)d + 18 Distribute 2d² + 12d + 3d + 18 Group and factor GCF 2d(d + 6) + 3(d + 6) Factor common binomial (d + 6)(2d + 3) Remember to check using FOIL! Slide 93 / 127 Factor. 15x² - 13x + 2 Slide 94 / 127 a = 15 and c = 2, but b = -13 Since both a and c are positive, and b is negative we need to find two negative factors of 30 that add up to -13 Factors of 30 -1, -30 -2, -15 -3, -10 -5, -6 Sum = -13? -1 + -30 = -31 -2 + -15 = -17 -3 + -10 = -13 -5 + -6 = -11 Slide 95 / 127 Factor 6y² - 13y - 5 Slide 96 / 127 Slide 97 / 127 A polynomial that cannot be written as a product of two polynomials is called a prime polynomial. Slide 98 / 127 53 Factor A B C D Prime Polynomial Slide 99 / 127 54 Factor A B C D Prime Polynomial Slide 100 / 127 55 Factor A B C D Prime Polynomial Slide 101 / 127 Factoring 4 Term Polynomials Return to Table of Contents Polynomials with four terms like ab - 4b + 6a - 24, can be factored by grouping terms of the polynomials. Example 1: ab - 4b + 6a - 24 (ab - 4b) + (6a - 24) b(a - 4) + 6(a - 4) (a - 4) (b + 6) Group terms into binomials that can be factored using the distributive property Factor the GCF Notice that a - 4 is a common binomial factor and factor! Slide 102 / 127 Example 2: 6xy + 8x - 21y - 28 (6xy + 8x) + (-21y - 28) 2x(3y + 4) + (-7)(3y + 4) (3y +4) (2x - 7) Slide 103 / 127 Group Factor GCF Factor common binomial You must be able to recognize additive inverses!!! (3 - a and a - 3 are additive inverses because their sum is equal to zero.) Remember 3 - a = -1(a - 3). Example 3: 15x - 3xy + 4y - 20 (15x - 3xy) + (4y - 20) 3x(5 - y) + 4(y - 5) 3x(-1)(-5 + y) + 4(y - 5) -3x(y - 5) + 4(y - 5) (y - 5) (-3x + 4) Slide 104 / 127 Group Factor GCF Notice additive inverses Simplify Factor common binomial Remember to check each problem by using FOIL. Slide 105 / 127 56 Factor 15ab - 3a + 10b - 2 A (5b - 1)(3a + 2) B (5b + 1)(3a + 2) C (5b - 1)(3a - 2) D (5b + 1)(3a - 1) 57 Factor 10m2n - 25mn + 6m - 15 A (2m-5)(5mn-3) B (2m-5)(5mn+3) C (2m+5)(5mn-3) D (2m+5)(5mn+3) Slide 106 / 127 Slide 107 / 127 58 Factor 20ab - 35b - 63 +36a A (4a - 7)(5b - 9) B (4a - 7)(5b + 9) C (4a + 7)(5b - 9) D (4a + 7)(5b + 9) 59 Factor a2 - ab + 7b - 7a A (a - b)(a - 7) B (a - b)(a + 7) C (a + b)(a - 7) D (a + b)(a + 7) Slide 108 / 127 Slide 109 / 127 Mixed Factoring Return to Table of Contents Summary of Factoring Slide 110 / 127 Factor the Polynomial Factor out GCF 2 Terms Difference of Squares 4 Terms 3 Terms Perfect Square Trinomial Factor the Trinomial a=1 Group and Factor out GCF. Look for a Common Binomial a=1 Check each factor to see if it can be factored again. If a polynomial cannot be factored, then it is called prime. Slide 111 / 127 Slide 112 / 127 60 Factor completely: A B C D Slide 113 / 127 61 Factor completely A B C D prime polynomial Slide 114 / 127 62 Factor A B C D prime polynomial Slide 115 / 127 Slide 116 / 127 64 Factor A B C D Prime Polynomial Slide 117 / 127 Solving Equations by Factoring Return to Table of Contents Given the following equation, what conclusion(s) can be drawn? Slide 118 / 127 ab = 0 Since the product is 0, one of the factors, a or b, must be 0. This is known as the Zero Product Property. Given the following equation, what conclusion(s) can be drawn? Slide 119 / 127 (x - 4)(x + 3) = 0 Since the product is 0, one of the factors must be 0. Therefore, either x - 4 = 0 or x + 3 = 0. x - 4 = 0 +4 +4 x = 4 or or x + 3 = 0 -3 -3 x = -3 Therefore, our solution set is {-3, 4}. To verify the results, substitute each solution back into the original equation. To check x = 4: (x - 4)(x + 3) = 0 To check x = -3: (x - 4)(x + 3) = 0 (-3 - 4)(-3 + 3) = 0 (-7)(0) = 0 0=0 (4 - 4)(4 + 3) = 0 (0)(7) = 0 0=0 What if you were given the following equation? How would you solve it? We can use the Zero Product Property to solve it. How can we turn this polynomial into a multiplication problem? Factor it! Factoring yields: (x - 6)(x + 4) = 0 By the Zero Product Property: x-6=0 or x+4=0 After solving each equation, we arrive at our solution: {-4, 6} Slide 120 / 127 Slide 121 / 127 Slide 122 / 127 Slide 123 / 127 Slide 124 / 127 65 Choose all of the solutions to: A B C D E F Slide 125 / 127 66 Choose all of the solutions to: A B C D E F Slide 126 / 127 67 Choose all of the solutions to: A B C D E F Slide 127 / 127 68 A ball is thrown with its height at any time given by When does the ball hit the ground? -1 seconds A B 0 seconds C 9 seconds D 10 seconds