Question

3x+y=-9
Y=5x+7
Solve the system of linear equations by substitution

Answer 1

x=-2

Explanation:

Substitute y=5x+7 into the equation 3x+y=-9

So you will have, 3x+5x+7=-9

3x+5x=8x

8x+7=-9

8x+7-7=-9-7

8x=-16

x=-2