Question

What is the solution to the system of equations? Use the linear combination method.

Answer 1

Answer:

(-4,15)

Step-by-step explanation:

Personally I think this works better with substitution, but I'll do it your way.

3x + y = 3

2x + y = 7               Subtract these two equations

x = - 4                      3 - 7 = - 4

3x + y = 3                 Substitute - 4 for x  

3(-4) + y = 3             Combine

-12 + y = 3                Add 12 to both sides

-12 + 12 + y = 3+12  

y = 15

Check

2x + y = 7

2*-4 + 15 = 7

- 8 + 15 = 7

7 = 7

It checks.