Question

Which expression can be substituted for y in the top equation of the

following system to solve the system by substitution? What is the solution?
3x - 5y = 1
3x - y = -7
I currently cannot download any files.

Answer 1

Y=7+3x, x=-3, y=-2

Explanation:

3x-5y=1. Equation 1

3x-y=-7. Equation 2

-y=-7-3x isolate for y in equation 2

y=7+3x multiplied by -1 to get positive y

3x-5(7+3x)=1 substitute y value of equation 2 (7+3x) into equation 1

3x-35-15x=1

-12x=36

x=-3

solve for y.

3x-5y=1

3(-3)-5y=1

-9-5y=1

-5y=10

y=-2