Question

Use linear combination method to solve this systemof equations. What is the value of x?

3x+7y=31
-3x-2y=-1

A)-6
B)-3 2/3
C)3 2/3
D)6

Answer 1

Using the linear combination method, we can add 3x+7y=31 and -3x-2y=-1 together, which makes 5y=30.

Just divide both sides by 5, and your answer will be y = 6.

To solve for x, just substitute 6 in y in either equation and solve for x:

`-3x-2(6)=-1\\ -3x-12=-1\\ -3x=11\\ x=-(11)/(3) =-3(2)/(3)`

In short, the correct answer is B. -3 2/3