Problem: 8x − 2 = y 5y − 12x = -3
Select the ordered pair from the choices below that is a solution to the following system of equations:
8x − 2 = y
5y − 12x = -3
1) 8x − 2 = y
2) 5y − 12x = -3
Equation 1 gives us the value of y, so substitute that
into equation 2.
5y − 12x = -3
5(8x − 2) − 12x = -3
40x - 10 - 12x = -3
28x - 10 = -3
28x - 10 + 10 = -3 + 10
28x = 7
28x/28 = 7/28
x = 7/28
x = 1/4
Now, solve for y.
8x − 2 = y
8(1/4) − 2 = y
2 - 2 = y
0 = y
And check.
5y − 12x = -3
5(0) − 12(1/4) = -3
0 - 3 = -3
-3 = -3
Answer: x = 1/4, y = 0
Ordered pair: (1/4, 0)