Question

In order to solve the following system of equations by subtraction, which of

Answer 1

Answer: I think it's C.Multiply the top equation by 3 and the bottom equation by 4

Step-by-step explanation:

Multiplying the top equation by 3 you get:

3(4x – 2y) = 3∗7

12x - 6y = 21          (eq.1)

Multiplying the bottom equation by 4 you get:

4(3x – 3y) = 4∗15

12x - 12y = 60       (eq.2)

Now, if you subtact eq.2 from eq.1 you get:

(12x - 6y = 21 )

-

(12x - 12y = 60)

___________________

0x + [- 6y -(-12y)] = 21 - 60

Carrying out the calculation you get:

6y = -39

y = -39/6

y = -13/2