Think & Click: Substitution Method
Now, you try. Complete the Think & Click activity by looking at each problem below, thinking about it, and then clicking on the question to reveal the solution.
x – 4y = -14
Solve the second equation for x: x = 4y – 14
Substitute this expression into the first equation for x: 3(4y – 14) + 2y = 14
Distribute and solve:
12y – 42 + 2y = 14
14y – 42 = 14
14y = 56
y = 4
Substitute this value in for y and solve for x: x – 4(4) = -14
x – 16 = -14
x = 2
Solution: (2, 4)
2x + 3y = -2
Solve the second equation for x: 2x = -2 – 3y, 
Substitute this expression into the first equation for x: 4(
) – 2y = 12
Distribute and solve:
-4 – 6y – 2y = 12
-4 – 8y = 12
-8y = 16
y = -2
Substitution this value in for y and solve for x: 2x + 3(-2) = -2
2x – 6 = -2
2x = 4
x = 2
Solution: (2, -2)
