Lucia tried to solve the system below. What error did she make?

{2x+2y = 14
{1x-2y=-2

Lucia's Work


x-2y=-2 2(-2-2y)+2y= 14
x=-2-2y -4-4y+2y=14 x-2(-9)=-2
-4-2y=14 x+18=-2
-4-2y=14 x=-20
-2y=18
y=-9