Question

Solve the system of equations using substitution. y = -7x 2x – y = -9

Answer 1

Answer:

x = -1

y = 7

Step-by-step explanation:

We have a system of equations and are asked to solve using substitution.

y = -7x

2x - y = -9

Since we have an equation for y by itself, we can plug the first equation into the second.

2x - (-7x) = -9

Distribute :

(-(-7x))

2x + 7x = -9

Add like terms :

9x = -9

Divide 9 by both sides to get x :

x = -1

Now that we know x, we can plug it into the first equation to find y :

y = -7(-1)

y = 7