Question

Y=4x-1

y=2x-5
It uses substitution and I know the answer, but I struggle with the process on how to get the answer.

Answer 1

(-2, -9) or x=-2, y=-9

Explanation:

First, isolate x in one of the equations.

y = 4x-1

y+1 = 4x

(y+1)/4 = x

Next, substitute in (y+1)/4 for x in the second equation.

y = 2x-5

y = 2[(y+1)/4]-5

y = (y+1)/2 - 5

At this point, break up your fraction so you can isolate y.

y = (y+1)/2 - 5

y = y/2 + 1/2 -5

y - y/2 = 1/2 - 5

y/2 = -9/2

y=-9

Finally, substitute -9 for y in either equation to find x.

y = 4x-1

-9 = 4x-1

-8 = 4x

x=-2

Your answer is (-2, -9) or x=-2, y=-9