Question

You want to solve the following system of equations by addition. What should

you do first, so that one variable is eliminated when you add the equations?
-2x+4y= 10
3x-2y=-7
OA. Multiply the top equation by 2 and the bottom equation by 3.
B. Multiply the top equation by 3 and the bottom equation by-2.
C. Multiply the bottom equation by 2.
D. Multiply the top equation by -3.
SUBMIT

Answer 1

Answer: C

Step-by-step explanation:

The two variables need to be eliminated. You can do this by multiplication or subtraction.

Multiply by -3 to the top equation will eliminate the x variable in the system

-3(2x - 4y = 5)

6x - 3y = 10

==> -6x + 12y = -15

6x - 3y = 10

adding a top with a bottom will eliminate the x

==> -6x + 6x = 0, 12y + (-3y) = 9y, -15 + 10 = -5