Question

Solve the system. y=x+2, y=-x+0.

Answer 1

Y = x + 2
y = -x

   x + 2 = -x
- x          - x
         2 = -2x
       -2     -2
        -1 = x
y = x + 2
y = -1 + 2
y = 1
(x, y) = (-1, 1)

Answer 2

Subsitute:
x+2 = -x
2x = -2
x = -1
Substitute back:
 y= -x = 1