What is the solution of the system? Use substitution.

3x + 2y = 7

y = - 3x + 11

A. (6, - 3)

B. (6, - 7)

C. (-4, 19/2)

D. (5, - 4)

Substitution is where you substitute, basically. So, substitute "y" for y.

They have given you y: - 3x+11.

They have also given you an equation for you to substitute y into: 3x+2y=7.

Now, you can create the substituted problem.

3x + 2 (-3x + 11) = 7

Use distributive property.

3x + - 6x + 22 = 7

Add like terms.

-3x + 22 = 7

Subtract 22 from 7.

-3x = - 15

Divide.

x = 5.

Now, that you have x, plug "5" back into the original equations or at least one of them to find your y.

I will do both to show you.

3 (5) + 2y = 7

15 + 2y = 7

2y = - 8

y = - 4

You would get - 4 with the other equation, too.

y = - 3 (5) + 11

y = - 15 + 11

y = - 4

Now, since you have x = 5, y = - 4, that would be equivalent to (5, - 4) which would be answer choice D.

*side note * because only one of the answer choices started with x being equivalent to y, you wouldn't need to go through finding y as the only possible answer choice could be D. However, it is always good to check and make sure you didn't do anything wrong with x by finding y. Also, I have done y for you not only in my benefit, but to show you what you would do if D wasn't so obvious when you only find x.