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
