810 Module 8 Study Guide Solving Systems of Equations Name:______________________ Period:__________ Vidal Alcock Feeney 1.) The school is selling tickets to the play. On the first day of ticket sales the school sold 1 adult ticket and 12 child tickets for a total of $60.60. The school took in $74.40 on the second day by selling 11 adult tickets and 6 child tickets. What is the price of one adult ticket and one child ticket? Define your variables: Set up your System and Solve: The price of one adult ticket is __________. The cost of one child’s ticket is __________. 2.) Huong and Mark are selling cheesecakes for a school fundraiser. French silk cheesecakes cost $12 each and chocolate marble cheesecakes cost $8 each. They sold a total of 15 cheesecakes and made a total of $160. How many of each type of cheesecake did they sell? Define your variables: Set up your System and Solve: They sold ___________ French silk cheesecakes and ___________ chocolate marble cheesecakes. You are trying to decide if you should get a cable TV package or a subscription to WebPix. Cable: You pay $100 for the installation and $50 per month for service. WebPix: You would need to buy a new TV for $200 and then pay a $25 per month membership fee. Let y be the cost of each plan Let x be the number of months of service. Write an equation for each plan. Cable _____________________ WebPix _____________________ Graph the system. y 700 600 Cost ($) 3.) 500 400 300 200 100 4 8 12 16 20 24 Months After how many months are the total costs of the plans the same? __________________ When is Cable better? ______________________________________________________ When is WebPix better? ______________________________________________________ x Solve the linear system by graphing. 1 y x 5 4.) 3 y 3x 5 6-8: Sketch a graph for the following situations and explain your reasoning. 6.) A system of two equations with only one solution. y y x x Explain: Will the line through the points (0, -3) and (-4, -3) intersect the following line? 5.) The line through the points (0 ,-2) and (3, -3) 7.) A system of two equations with no y solution. y x x Explain: 8.) A system of two equations with infinitely many solutions. y x Explain: Use substitution to solve the following: 𝑦 = −4𝑥 − 11 9.) { −4𝑥 − 2𝑦 = 6 10.) { 4𝑥 + 7𝑦 = 13 𝑥 = 3𝑦 − 11 Use elimination to solve the following: 11.) { 5𝑥 − 6𝑦 = −17 −8𝑥 + 6𝑦 = 20 12.) { 7𝑥 − 8𝑦 = −4 −10𝑥 + 10𝑦 = 10 Answer the following for the system below: −11𝑥 + 𝑦 = −22 13.) { −16𝑥 − 2𝑦 = −32 a.) Describe the first step if you were to solve with elimination: b.) Describe the first step if you were to solve with substitution: