Question 168126
if you add these 2 equations together you would be adding the x terms to x terms the y terms to the y terms and the constants to the constants.

so 2x+2x=4x--->y+(-y)=0 and 18+22=40

so your left with 4x=40 or x=10

now plug x's value back into either of the original equations to find y

I choose the 1st  2(10)+y=18  subtract 20 from either side and you get y=-2