1. y = -2x + 4 y = x2 + x - 6 2. y = x - 2 y = x2 - 3x + 2

1. 
y = -2x+4 disubstitusikan ke persamaan y = x²+x-6
-2x+4 = x² + x - 6
x² + x - 6 + 2x - 4 = 0
x² + 3x - 10 = 0
(x + 5)(x - 2) = 0
x +5 = 0
x = -5
atau
x-2=0
x = 2

2.
y = x - 2 disustitusikan ke pers. y = x² - 3x + 2
x-2 = x² - 3x + 2
x² - 3x + 2 - x + 2 = 0
x² - 4x + 4 = 0
(x - 2)(x - 2) = 
x - 2 = 0
x = 2