Set equal to each other
x^2 - 8 = 2x
x^2 - 2x - 8 = 0
Factor
(x - 4)(x + 2) = 0
x = 4 or x = -2
Plug in 4
y = 2x or y = x^2 - 8
y = 2(4) or y = 4^2 - 8
y = 8
Plug in -2
y = 2x or y = x^2 - 8
y = 2(-2) or y = (-2)^2 - 8
y = -4
There are two solutions
(4, 8) and (-2, -4)
