American Certificate (ACT/EST) Final Revision 4 Edition th Name: ……………………………… Phone: ……………………………… Centre: ……………………………… Eng\ Kariom Alaa Eldin Mob:010 3397 2664 Date: / Contents Introduction ...................................................................................................... 3 The Language of Algebra................................................................................... 3 Chapter 1 : Linear Equations ............................................................................. 4 Chapter 2 :Statistics and Data Analysis ........................................................... 12 Chapter 3 Law of Exponents and Polynomials ................................................ 17 Chapter 4 : Quadratic Functions ..................................................................... 19 The imaginary number .................................................................................... 24 Chapter 5 :Composition of Functions ............................................................. 25 Chapter 6 Direct and Inverse Variations ......................................................... 29 Chapter 7 :Trigonometric Functions ............................................................... 30 Chapter 8 : Geometry ..................................................................................... 31 2|Page ENG. Karim Alaa Date: / For Example There is no simplifying between two different variables 3|Page ENG. Karim Alaa Date: / An equation is a mathematical sentence with an equal sign. To translate a word sentence into an equation, choose a variable to represent one of the unspecified numbers or measures in the sentence. This is called defining a variable. Then use the variable to write equations for the unspecified numbers. 4|Page ENG. Karim Alaa Date: / Some equations have variables on both sides. To solve such equations, first use the Addition or Subtraction property of Equality to write an equivalent equation that has all of the variables on one side. Then use the multiplication or Division Property of Equality to simplify the equation if necessary. When solving equations that contain grouping symbols, use the Distributive Property to remove the grouping symbols Use (shift solve) if you have only one missing from first degree And (mode 5eqn 3) if you have one unknown from 2nd degree 5|Page ENG. Karim Alaa Date: / Y=c x=c The slope-intercept form of the equation of a line is 𝐴𝑥 + 𝐵𝑦 = 𝐶, in which −𝐴 𝐵 𝐶 is the slope and is the y𝐵 intercept. 𝑦 = 𝑚𝑥 + 𝑏 , in which m is the slope and b is the yintercept. 6|Page ENG. Karim Alaa Date: / Parallel and Perpendicular Lines Lines in the same plane that do not intersect are called parallel lines. Parallel lines have the same slope. If two nonvertical lines have the same slope, then they are parallel For example: Write the equation in point-slope form of the lines through point(1,2) that are (a) parallel to (b) perpendicular to, 3x-y=-2 Sol. a=3 b=-1 −𝑎 𝑏 = − 3 −1 finding the coefficients =3 7|Page calculating the slope ENG. Karim Alaa Date: / A) B) Y=mx+c finding the equation Y=3x+c 2=3*1+c c=-1 Y=3x-1 Y= mx+c −1 𝑦 = 𝑥+𝑐 3 𝑦= −1 𝑥 3 −1 × 3 2= 1+𝑐 7 +3 Use: (mode 5 eqn 1) to get the solution Or 8|Page ENG. Karim Alaa Date: / NO solution Zero intersection infinite solutions many intersections Ax+by=c Mx+ny=k Ax+by=c Mx+ny=k Use 𝑎 𝑏 =𝑛 𝑚 9|Page Use 𝑎 𝑏 𝑐 =𝑛=𝑘 𝑚 ENG. Karim Alaa Date: / 10 | P a g e ENG. Karim Alaa Date: / Solving Word Problems Using Linear Models In SAT verbal problems, the construction of mathematical models that represent real-world scenarios is a critical skill. Linear equations can be used to model many types of real life situation word problems, such as cost, profit, speed, distance and time problems. To solve the verbal problems, you need to interpret the situation described in the problem into an equation, then solve the problem by solving the equation. Plan for Solving a Word Problem 1. Find out what numbers are asked for from the given information. 2. Choose a variable to represent the number(s) described in the problem. Sketch or a chart may be helpful. 3. Write an equation that represents relationships among the numbers in the problem. 4. Solve the equation and find the required numbers. 5. Answer the original question. Check that your answer is reasonable. 11 | P a g e ENG. Karim Alaa Date: / 12 | P a g e ENG. Karim Alaa Date: / The word percent means hundredth or out of every hundred. To write a decimal or a fraction as a percent, multiply the decimal or the fraction by 100 and add the % sign. Convert the fraction to decimal. To write a percent as a decimal or a fraction, multiply the percent by , and 1 drop the % sign. 100 Simplify the fraction. 13 | P a g e ENG. Karim Alaa Date: / 14 | P a g e ENG. Karim Alaa Date: / 15 | P a g e ENG. Karim Alaa Date: / 16 | P a g e ENG. Karim Alaa Date: / 17 | P a g e ENG. Karim Alaa Date: / 𝑛 𝑚 √𝑥 𝑚 = 𝑥 𝑛 18 | P a g e 5 2 √𝑥 2 = 𝑥 5 ENG. Karim Alaa Date: / 19 | P a g e ENG. Karim Alaa Date: / The standard form of a quadratic function y=f(x) can be written in the form f(x)=ax2+bx+c, in which 0≠a. The graph of a quadratic function is called a parabola. If 0>a, the graph opens upward and the vertex is the minimum point. If 0<a, the graph opens downward and the vertex is the maximum point. The maximum or minimum point of a parabola is called the vertex. The equation of the axis of symmetry is 𝑥 = −𝑏 2𝑎 The coordinates of the vertex are ( −𝑏 2𝑎 ,f( −𝑏 2𝑎 )) The vertex form of a quadratic function can be written in the form f(x)=a(x-h)2+k , in which (h,k) 20 | P a g e ENG. Karim Alaa Date: / The factored form of a quadratic function can be written in the form f(x)= a(x-L)(x-M) 𝑙+𝑚 roots. vertex =( 2 𝑙+𝑚 ,𝑓( 2 )) To factorize the quadratic y=x2 - sum x +product The solutions of a quadratic function are the values of x for which f(x) =0. Solutions of functions are also called roots or zeros of the function. On a graph, the solution of the function is the xintercept(s). To find the y-intercept of a parabola, let x equal to zero in the equation of the parabola and solve for y. If the parabola has two x-intercepts, then the x-intercepts are equidistant from the axis of symmetry. 21 | P a g e ENG. Karim Alaa The sum of roots equals Date: / −𝑏 𝑎 The product of roots equals 𝑐 𝑎 Determining the type of roots for the second degree equation. There are 3 types. Use the Discriminant to know: 𝑏 2 − 4𝑎𝑐 22 | P a g e ENG. Karim Alaa Date: / 23 | P a g e ENG. Karim Alaa Date: / ''i" is defined as the number whose √−1 = 𝑖 i.e. 𝑖 2 = −1 i2 = - 1 i1 = √−1 i3 = - i i4 = 1 If we have an 'i' with a power greater than 4 what we'll do in divide n by 4 𝑛 4 = 𝑎. 𝑏 take the decimal value b and multiply it by 4 for Example: i23 23 4 = 5.75 then 0.75×4=3 so, i23 =i3 = -i 24 | P a g e ENG. Karim Alaa Date: / Complex numbers consist of two parts (real + img) a + bi real img no no Two Complex numbers are equal if and only if( ⟺) the two real parts are equal and the two imaginary parts are equal. i.e. if : (a + bi) and (c + di) are two Complex numbers and if : a = c , b = d , then : a +bi = c + di and vice versa : if : a + bi = c + di , then : a = c , b = d The two numbers : (a + bi) and (a – bi) are called Conjugate numbers. Note : Take care that the Complex number and its Conjugate differ only in the sign of their imaginary parts. 25 | P a g e ENG. Karim Alaa Date: / 26 | P a g e ENG. Karim Alaa Date: / Exponential Growth and Decay Compound Interest Formulas If initial amount P is invested at annual interest rate r, the investment will grow to final amount A in t years. 𝐴 = 𝑃(1 + 𝑟)𝑡 We can use the same formula for the population or value of goods that is increasing or decreasing. 27 | P a g e ENG. Karim Alaa Date: / Finding the nth Term of an Arithmetic Sequence Tn = a1 + (n - 1)d Where: Tn is the nth term in the sequence a1 is the first term n is the number of the term d is the common difference Infinite Arithmetic series 28 | P a g e ENG. Karim Alaa Date: / 29 | P a g e ENG. Karim Alaa Date: / A ratio of the lengths of sides of a right triangle is called a trigonometric ratio. 30 | P a g e ENG. Karim Alaa Date: / 𝛱=180 For not right angled triangle 1 Area= x S1 x S2 sin(θ) 2 In any triangle the sum of two smaller sides is greater the biggest one 31 | P a g e ENG. Karim Alaa Date: / Regular Polygons A regular polygon is a convex polygon with all sides congruent and all angles congruent. A polygon is inscribed in a circle and the circle is circumscribed about the polygon where each vertex of the polygon lies on the circle. The radius of a regular polygon is the distance from the center to a vertex of the polygon. A central angle of a regular polygon is an angle formed by two radii drawn to consecutive vertices. The apothem of a regular polygon is the distance from the center to a side. 32 | P a g e ENG. Karim Alaa Date: / Circles 33 | P a g e ENG. Karim Alaa Date: / 34 | P a g e ENG. Karim Alaa Date: / X2+y2+ax+by+c=0 Center = ( −𝑎 −𝑏 2 , 2 ) −𝑎 −𝑏 2 2 Radius = √( )2 + ( )2 − 𝑐 35 | P a g e ENG. Karim Alaa Date: / 36 | P a g e ENG. Karim Alaa