Name ________________________________ Algebra 2 Exam Review Part 1 – December 2015 All correct algebraic support is required for credit. Show work on a separate piece of paper. 12. Solve the following inequality for w. 1. Solve │x + 9│ > 15 2. Solve │x + 5│ = 8 2 8 3w 13 5 Write the solution set for the 3 3. The horizontal bar used in gymnastics events should by placed 110.25 inches above the ground, with a tolerance (margin of error) of 0.4 inches. Write an absolute value inequality for the acceptable heights. 4. A battery operated car, the Tesla Model S, has a cost that ranges from $69,900 to $104,500 depending on the battery capacity. Write an absolute value equation describing the maximum and minimum cost. 5. The recommended oven setting for cooking a pizza in a professional brick-lined oven is between 550 degrees F and 650 degrees F, inclusive. Write an absolute value inequality for this temperature range. 6. A car is 500 feet from Krista and driving toward her at 32 feet per second. At what times will the car be exactly 50 feet from her? Write and solve an absolute value equation for this situation. 7. What is the 8. Given: solution of 2│x│ < -4 ? 5 2 x 1 3 10 Which is the solution set for x? 9. Given the following absolute value equations or inequalities: I 1 7 9 x2 4 8 16 II III 5 x 1 4 16 10.1 x 4.3 10.1 Which of these have no solution? 10. Solve │x - 4│ = -12 11. Solve │x + 4│ ≥ -20 function as an inequality, as an interval, in set notation and on a number line, 13. Write an absolute value inequality to describe the graph. Write an absolute value inequality that would take 3 or more steps to solve to describe the graph. 14. A speech teacher has 24 students in her class. She has 50 minute periods and has set 3 class periods aside for her students to give their final speeches. If she has given each of her students a minimum time requirement of 3 minutes per speech and a maximum based on her amount of time and number of students, write an absolute value function would represent the minimum and maximum speech times, t. 15. Solve the absolute value equation. Graph the solution on a number line. 16. What is the sum of the solutions of ? 17. What is the graph of the absolute value equation given? 18. Graph the function coordinates of the vertex. and find the 19. Determine how many units and in which direction the function translates the parent function . 20. Find the x and y intercepts of the function . 21. Find the domain and range of the function . 22. Explain how the equation of the line of symmetry relates to the equation of an absolute value function . The equation for the line of symmetry is ________. The line of symmetry occurs when x equals _____. 23. Find the equation of the line of symmetry for the function 30. Graph the function x-axis. reflected about the 31. Compare the function, 𝑦 = |− 7𝑥 + 3| + 6, with the parent function. Determine the vertex, axis of symmetry and transformations of the parent function. . 32. Plot set of axes. 24. Determine the range for each function. A f x 2 x 3 5 B f x 2 x 5 3 C f x 2 x 5 3 D f x 2 x 3 5 and on the same 33. Given an absolute value function, f x x 4 3 , give 4 functions that would share the same maximum point. Use each of the following representations, graph, table, equation using function notation and equation using y = . 25. Find the maximum value of the interval . on 34. An absolute value function, f(x), is given below. Write an absolute value equation would have at least one equivalent x-intercept as f(x). 26. A student records the height of the water in a pool each day for seven days. The same amount of water is removed from the pool each day for four days. Then the same amount of water is added into the pool for the last three days. The function models the height of the water h (in feet) in the pool after t days. Find the domain and range for this function and interpret their meaning in the context of the problem. 27. Describes the translation of ? to 35. Graph the absolute value equation given 28. What is the equation of the absolute value function graphed below? 12 y 8 4 –10 –8 –6 –4 –2 2 x –4 –8 –12 –16 29. Which transformations to the graph of f x 3 x 2 1 create a function whose vertex is 2,1 ? 36. A student records the height of a toy submarine for 10 seconds. The function ℎ(𝑡) = −|𝑡 − 5| − 10 models the height h (in feet) of the submarine after t seconds. What is the difference between the submarine’s greatest height and least height during the 10 second period? 37. A company produces widgets that are 2.25 inches tall and they are manufactured with the following tolerance: |𝑙 − 2.25| ≤ 0.08. The widgets are stacked for storage to a target stack length of 96.75 inches with tolerance |ℎ − 96.75| ≤ 0.5. What is the maximum possible number of pellets in a stack? 38. 39. Which inequality does the graph represent? 45. Solve the system. 46. Solve the system. 𝑦 = 𝑥 2 − 12𝑥 + 36 { 𝑥 + 𝑦 = 18 40. The shaded area below contains the points that 3 satisfy both of the inequalities 𝑦 ≤ 4 − |𝑥 − 1| and 2 𝑦 ≥ 𝑎. What is the value of a? 47. Write an equation for a quadratic function if the graph has a vertex at (3, 5) and is stretched vertically by a factor of 2? 48. Matt has a neighborhood lawn business for the summer. He has a weekly schedule where he can mow at most 20 lawns per week and weed at most 8 lawns per week. Matt charges $10 for each lawn mowed and $55 for weeding each yard. If m represents the number of lawns mowed and w represents the number of lawns weeded, write a system of inequalities would represent all the possible lawns that will earn Matt at least $400 per week? 49. Which quadrants contain the solutions to this system of inequalities? y0 41. Assume that x and y are whole numbers. Use a table to solve the system of inequalities. y 5 x 14 4 x 7 y 28 42. Solve the system by substitution 𝑦 = 13 − 3𝑥 { 2𝑥 + 9𝑦 = −8 43. Solve the system by graphing. 6𝑥 + 𝑦 = 31 { 𝑥 + 5𝑦 = −19 50. Find the sum of the x-coordinates of the solutions to the system of equations. –x + y = 2 Y = x2 – 4 51. A right triangle is formed below. Write a system of inequalities that would represent 44. In 1972, city #1 and city #2 had the same population. The population of city #2 continued to increase steadily, while the rate of population growth of city #1 (although initially less than that of city #2) eventually overtook the growth rate of city #2. The populations of two cities are modeled by the following equations: City #1 City #2 𝑦 = 2𝑥 2 + 15𝑥 + 1080 𝑦 = 25𝑥 + 1080 where x=0 corresponds to the year 1972. In what year after 1972 did the cities have the same population? the triangle. 52. Your club is baking vanilla and chocolate cakes for a bake sale. They need at most 22 cakes. You cannot have more than 8 chocolate cakes. Write and graph a system of inequalities to model this system. Let x = the number of vanilla cakes. Let y = the number of chocolate cakes. 53. The table on the next page contains solutions to a system of inequalities. Write two possible systems. x -3 -2 0 1 y 1 4 3 2 54. Solve the system of inequalities by graphing. 57. Two skaters are practicing at the same time on the same rink. One skater follows the path 𝑥 2 + 𝑦 2 = 45, while the other skater follows a straight path that begins at ( - 1, - 2) and ends at (5, 10). Which of the following best describe this situation? A The skaters will not cross paths while practicing because the functions that represent their paths do not intersect. B The skaters will cross paths once at (3, 6) because the skaters path begins at ( - 1, - 2). C The skaters will cross paths twice, at (-3, - 6) and (3, 6) because the linear function through at ( - 1, - 2) and (5, 10) has a domain of all real numbers. D The skaters will cross paths once at (5, 45) because the skaters path ends at (5, 10). 58. Solve the system of inequalities by graphing. 55. Jana graphs the system of constraints to find the minimum value of an objective function. Explain Jana’s error. 59. When using Gaussian elimination to solve a system of three variables, why is it important to have all 0’s, except for a single 1, in each row, except for the last element? 56. If Jana correctly calculates the maximum value given the objective function 𝑃 = 3𝑥 + 4𝑦. What is the maximum value she calculated? A The 0’s represent the value of the variables being solved for. The 1’s represent the values of the other variables. These rows represent the coefficients of the variables. B Each 1 represents the value of the variable being solved for. The 0’s are the values for the other variables. These rows represent equations in which every variable except one has been eliminated. C The 0’s represent the coefficient of the variable being solved for. The 1’s are the other variables’ coefficient. These rows represent the coefficients of the variables. D Each 1 represents the coefficient of the variable being solved for. The 0’s are the other variables’ coefficient. These rows represent equations in which every variable except one has been eliminated. 4𝑥 + 4𝑦 + 4𝑧 = −4 3𝑥 + 5𝑦 + 4𝑧 = 0 2𝑥 + 2𝑦 + 5𝑧 = 7 { 67. Write a matrix equations that can be used to represent the system below? 60. Write the system of equations represented by the augmented matrix below. 0 2 6 4 0 1 4 5 1 2 7 1 { 61. The augmented matrix for a three variable 0 2 6 4 system is 0 1 4 5 . Pablo uses 1 2 7 1 Gaussian elimination and determine the 1 0 0 6 augmented identity matrix is 0 1 0 7 . 0 0 1 3 What is the solution to the system? Write your answer as an ordered triple. 62. Write an augmented matrix that can be used to represent the system below? 63. Solve the following system, then give the value of x. 𝑥 + 4𝑧 = 43 𝑦 + 2𝑧 = 18 −3𝑦 + 𝑧 = 2 { 64. Solve the following system, then give the value of z. 1𝑥 + 1𝑦 − 1𝑧 = 4 𝑦=6 6𝑥 − 𝑦 + 3𝑧 = −9 { 65. Solve the following system. Give you answer as an ordered triple. −2𝑥 + 𝑦 + 3𝑧 = −2 𝑧=5 𝑥 − 2𝑦 = 10 { 66. Solve the following system, then give the value of y. 68. Maria has some 49¢ stamps, some 32¢ stamps and some 25¢ stamps worth $25.65. The number of 25¢ stamps is 10 less than the number of 32¢ stamps. The number of 49¢ stamps is twice the number of the other stamps combined. If x, y, and z represent the number of 49¢, 32¢, and 25¢ stamps respectively, which system of inequalities could be used to solve for the number of 25¢ stamps that Maria has? 69. A food store makes a 11-lb mixture of oatmeal (x), crispies (y), and chocolate chips (z). The cost of oatmeal is $1.00 per pound, crispies cost $3.00 per pound, and chocolate chips cost $2.00 per pound. The mixture calls for twice as much oatmeal as crispies. The total cost of the mixture is $19.00. Write a system of equations that could be used to find out how much of each ingredient did the store use? 70. A food store makes a 7-lb mixture of peanuts, almonds, and raisins. The cost of peanuts is $1.00 per pound, almonds cost $3.00 per pound, and raisins cost $1.00 per pound. The mixture calls for twice as many peanuts as almonds. The total cost of the mixture is $9.00. How much of each ingredient did the store use? 71. The coach purchased a combined total of 58 small, large, and extra-large shirts for $1411. The sum of twice the number of small and the number of extra-large is five times the number of large shirts. The cost of each is shown below: Small shirts cost $18.00 each Large shirts cost $22.50 each Extra-large shirts cost $25.00 each Based on this information, give two possible reasonable number of large shirts that he purchased? 72. The following matrix equation can be used to represent a system of equations. What are three different possible first steps if you were solving the system using Gaussian elimination? drinks, d, and quarts of ice cream, q, she bought. 8 2 4.5 p 105 8 1 0 d 0 1 0 2 q 0 If Nicole bought enough drinks for each person at the party to have exactly two drinks, how many people were at the party? 73. Nicole spent $105 to buy a combination of pizza, drinks and ice cream for a party. Each pizza cost $8, each drink cost $2, and each quart of ice cream cost $4.50. For every pizza she bought, she bought 8 drinks. She bought 1 quart of ice cream for every 2 pizzas. The matrix equation below can be used to determine how many pizzas, p, 75. Megan solved the following absolute value. 74. Write the system as an augmented matrix. Then identify the coefficient matrix and the constant matrix. 2 x 1 x 3x 4 In which step did Megan first make a mistake? Step 1 2 x 1 4x 4 Step 2 x 1 2x 2 Step 3 x 1 2x 2 or x 1 2x 2 1 x 2 or 3x 1 2 3 x or 3x 1 Step 4 Step 5 Step 6 Step 7 x 3 or x 1 3 1 3, 3 76. The steps shown below, use Gaussian elimination to solve the system: Finish the problem to solve for y. 2 0 3 14 2 6 7 24 0 2 3 11 Procedure Math Result -2 0 3 14 Multiply row 1 2 0 3 14 by -1 and add 0 6 10 38 2 6 7 24 to 0 6 10 38 0 2 3 11 row 2; replace row 2 Multiply row 3 by -3 and add to row 2; replace row 3 Multiply row 3 by 3 and add to row 1; take half and replace row 1 0 6 9 33 0 6 10 38 0 0 0 0 2 2 1 3 5 15 0 3 14 0 0 1 1 2 2 0 3 14 0 3 5 19 0 0 1 5 1 0 0 0.5 0 3 5 19 0 0 1 5