System of Equations
Given the equations:

Solve it by substitution.
Since the y is isolated in both equations, we just substitute one into the other equation as follows:

Adding 5 and subtracting 4x:

To find the value of y, just substitute x = -2 in any of the equations:

If we had used the second equation, we would have gotten the very same result.
Answer: (-2, -9)