Question

Solve 2x-y=7
5x-4y=22

Answer 1

\[x=2,y=-3\]

Answer 2

\[8x-4y=28\]
\[5x-4y=22\]

Change the signs so \[-8x+4y=-28\].

Add the equations like a regular problem, canceling out the y and leaving -3x=-6, or x=2.
Plug x back in the equation, and get 2(2)-y=7 or y=-3.

Answer 3

Whoops, the first step should say multiply the top equation by 4 so the y cancels out.

Answer 4

THANKS!