Page 199 - Math Course 2 (Book 1)
P. 199

Methods of Solving Systems of Equations






                CAR RENTAL                                        You can use elimination to solve.
                Ace Car Rental rents a car for $45 a
                day and $0.25 per mile. Star Car Rental                y = 45 + 0.25x
                rents a car for $35 per day and $0.30 per mile. How   (–)y = 35 + 0.30x
                many miles would a driver need to drive before the        0 = 10 – 0.05x
                cost of renting a car at Ace Car Rental and renting a   –10 = –0.05x
                car at Star Car Rental were the same?
                                                                  200 = x
                Explore
                You know the cost to rent a car for each company.                 This means that after 200 miles,
                                                                      Answer
                                                                                     the cost will be the same.
                Plan
                Write an equation to represent the cost for each
                company. Then solve.                              Check
                                                                  Check by sketching a graph of the equations.
                Solve                                             The graphs appear to intersect at (200, 95) which
                Let x = the number of miles and y = the cost of   verif es that x = 200.
                renting a car.
                Ace Car Rental:  y = 45 + 0.25x
                Star Car Rental: y = 35 + 0.30x


                 Your Turn!


                Determine the Best Method

                 POOL PARTY                                        VIDEO GAMES
                 At the school pool party, Mr. Lewis bought 1 adult   The cost to rent a video game from Action Video
                 ticket and 2 child tickets for $10. Mrs. Vroom    is $2 plus $0.50 per day. The cost to rent a video
                 bought 2 adult tickets and 3 child tickets for $17.   game at TeeVee Rentals is $1 plus $0.75 per day.
                 All adult tickets are the same price and all child   After how many days will the cost of renting a
                 tickets are the same price. The following system   video game at Action Video be the same as the
                 can be used to represent this situation. Determine   cost of renting a video game at TeeVee Rentals?
                 the best method to solve the system of equations.
                 Then solve the system.                            A. 8 days
                 x + 2y = 10                                       B. 4 days
                 2x + 3y = 17                                      C. 2 days
                                                                   D. 1 day
                 A. (4, 3)                                          Answer
                 B. (4, 4)
                 C. (3, 3)
                 D. (–4, –3)

                  Answer





















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