-6x-24y=-63

-6x - 24y = -63

 6x -   4y = 14           add the equations  giving us

- 28x =  - 49        divide both sides by - 28

x = 49 / 28 =   7/2      sub this into either equation to find y

6(7/2) - 4y  = 14

21 - 4y  = 14

-4y  = 14 - 21

-4y  = - 7       divide by - 4

 y =  7/4