At the first track meet, Bobby threw the shot put feet. At the second track meet he threw the shot put feet. Which of the following expressions could be used to find the distance he improved his throw from the first track meet to the second track meet?

A. | 42 3/4 + 44 1/2 |

B. | 42 3/4- (-44 1/2 |

C. | 44 1/2- ( -42 3/4

D. | 42 3/4 - 44 1/2 |

So the first thing we do is to multiply the top equation by 3. the reason i want to do this is i notice there will be a 6y on both equations and can possibly add/subtract them. so we get 6y = -3x + 27. adding that and the second equation we get 6x = 27-15 which is 12. divide by 6 and we get 2. ∴ x = 2. substituting 2 into the first equation we get 2y = -2 + 9 which is 7. divide by 2 and we get 7/2. ∴ y = 7/2, x = 2.

The answer is