To solve this pair of equations, by using the substitution method, all you have to do is simply choose 1 equation and simply solve for any variable X and or y. Then solve for the other equation, by plugging in the equation. 
Y = X + 4 
Y = -2x - 2 
X + 4 = -2x - 2 
0 = -3x - 6 
-3x = 6 
X = -6/3 
X = -2. 
Y = X + 4 
Y = -2 + 4 
Y = 2. 
P(-2,2). The following point would be the solution to the equation.