MATH 082 FINAL - PRACTICE TEST #1 Revised 06/23/09 Give all answers in simplest form. 1. Simplify. Write all answers without negative or zero exponents. 2. Simplify the expression by combining like terms: 3. Solve for x: 18 – 4(2x – 3) + 5x = 41 2 1 1 4 4. Solve for x: 3 x + 4 = 6 x – 3 5. Solve the inequality and graph the solution: -4x + 3 < 11 6. Solve for A if L = A + (M – 1)D. Given L = 29, M = 6, D = 5. 7. Solve for : 3 8. Graph the line whose slope is 4 and is . 9. Find the slope of the line passing through the points (1, -2) and (-3, 10) 10. The slope of a line is 2 and one point on a line is (- 1, 3). Find the equation of the line and write the answer in slope-intercept form. 11. Write the equation of the line that passes through the points (-3, 11) and (1, 3). In problems 12 & 13, solve the system of equations. 12. 2x – y = 5 5x + 3y = 18 13. y = 3x + 2 4x – y = 0 14. Simplify (2xy3) 4 251 Math 082 Final - Practice Test #1 cont. 15. a). Write 350 in Scientific Notation b). Convert to decimal notation. c). Multiply. Give your answer in scientific notation form. 16. Multiply: 17. Multiply and simplify: (4x – 3y)(2x + 5y) 18. Simplify: (3x 4) 2 19. Factor completely: 2x3y– 6x2y+ 2xy 20. Factor completely: x2 + 4x – 21 21. Factor completely: x2 – 49 22. Solve for x by factoring: x 2 3 x 28 0 23. Translate into an equation using one variable and solve: the sum of 5 times a number and nine is three less than the product of two and the number. 24. Solve by graphing: y 2x 4 3x 2 y 6 25. I bought 3 notebooks and 5 folders for my classes and spent $25. My friend, Alex, bought 8 folders and 5 notebooks and spent $41. Set up a system of equations that models the situation and solve the system to find the cost of each notebook and folder. 252 PRACTICE TEST SOLUTIONS 1. 2. = = Distribute the -2 combine like terms 3. 18 – 4(2x - 3) + 5x = 41 18 – 8x + 12 + 5x = 41 -3x + 30 = 41 -3x = 11 11 x=3 2 1 1 4 4. 3 x + 4 = 6 x – 3 ; Distribute the -4 Combine like terms Subtract 30 from both sides of the equation Divide both sides of the equation by -3 Find the common denominator. Then multiply the common denominator by each term of the equation. 2 1 12 · 3x + 12 · 4 8x + 3 = 2x – 16 6x + 3 = -16 6x = -19 -19 x= 6 1 -4 = 12 · 6x + 12 · 3 Subtract 2x from both sides of the equation Subtract 3 from both sides Divide both sides of the equation by 6 5. -4x + 3 < 11 -4x < 8 x > -2 6. L = A + (M – 1)D L = 29, M = 6, D = 5 Subtract a 3 from both sides Divide both sides by -4 and flip the inequality symbol 29 = A + (6 – 1) . 5 Substitute the given values 29 = A + 25 Subtract (6 – 1), then multiply by 5 (PEMDAS, Use correct order of operations,) A=4 Subtract 25 from both sides of the equation 7. Subtract from both sides divide both sides by 3 253 Math 082 Final - Practice Test #1 cont. 8. y 3 x3 4 10 8 Graph the line by Plotting Points: 6 4 x y 0 -3 4 0 2 3 y (0) 3 0 3 3 4 -10 -8 -6 -4 -2 2 4 6 8 10 -2 -4 3 y (4) 3 3 3 0 4 -6 -8 -10 Graph the line using the Slope and Y-intercept: The slope of the line is ¾ and the y-intercept is –3. Plot the y-intercept (0, -3). Then use the slope to find other points on the line. Starting at (0, -3) rise 3 and run 4 (Move up 3 and right 4). Repeat this (Move up 3 and right 4) to find additional points on the line. 9. slope = 10 – (-2) 10 + 2 12 -3 – 1 = -3 – 1 = -4 = -3 10. y mx b , y 2 x b , since m 2 Then, use the point (-1 , 3) in y = 2x + b to solve for b. 3 = (2)(-1) + b, 3 = - 2 + b, Add 2 to both sides of the equation 5 = b Equation: y = 2x + 5 11. First, calculate the slope. m= = = = -2 Then, use the point (1 , 3) in y = -2x + b to solve for b. y = mx + b 12. 2x – y = 5 5x + 3y = 18 Solution: (3,1) 3 = (-2)(1) + b 6x – 3y = 15 5x + 3y = 18 11x = 33 x =3 3 = -2 + b +2 +2 5 = b Equation: y = -2x + 5 Multiply by 3 2(3) – y = 5 Add down 6–y=5 Divide by 11 on both sides – y = -1 Substitute x = 3 into original equation to find y y=1 254 Math 082 Final - Practice Test #1 cont. 4x – (3x + 2) = 0 Substitute 3x + 2 for y 4x – 3x – 2 = 0 Distribute the – x – 2 = 0 Combine like terms x = 2 Add 2 to both sides 13. y = 3x + 2 4x – y = 0 Solution: (2,8) Substitute x = 2 into original equation to find x 14. (2xy3) 4 =16x4y12 15. a) 3 5 0 = 3.5 x 102 b) c) 16. 17. (4x – 3y)(2x + 5y)= 8x2 + 20xy– 6xy –15y2 = 8x2 +14xy – 15y2 18. (3x 4) 2 (3x 4)(3x 4) 9 x 2 12 x 12 x 16 9 x 2 24 x 16 19. Greatest Common Factor = 2xy 2x3y– 6x2y+ 2xy =2xy(x2 – 3x + 1) 20. c = -21 x2 + 4x – 21 = x2 – 3x + 7x – 21 = x(x – 3) + 7(x – 3) = (x – 3)(x + 7) 21. Factor a Difference of Two Squares: x2 – 49 = (x)2 – (7)2 = (x + 7)(x – 7) 22. x2 – 3x – 28 = 0 Factor using the AC test (A = 1, B=-3, C=-28) ( x 4)( x 7) 0 Set each factor equal to 0 x – 7 = 0 x + 4 = 0 Solve each equation x=7 x = -4 23. Let x the number, translate the statement into a mathematical equation: 5x 9 2 x 3 3x 12 y = 3(2)+2 y = 6+2 y=8 subtract 2x and 9 from both sides 255 Math 082 Final - Practice Test #1 cont. 24. Graph the lines the equations y 2 x 4 and 3x 2 y 6 , then find the intersection point between two lines. solution: 25. Let x = the cost of one notebook y = the cost of one folder 3x + 5y = 25 5x + 8y = 41 15x + 25y = 125 Multiply by 5 -15x – 24y = -123 Multiply by -3 y=2 Substitute into original equation The cost of one notebook = x = $5 and The cost of one folder = y = $2 256 3x +5(2) = 25 3x + 10 = 25 3x = 15 x=5