In order to solve the following system of equations by subtraction, which of the following could you do before subtracting the equations so that one variable will be eliminated when you add them?
4x+2y=7
3x-3y=15

Question

In order to solve the following system of equations by subtraction, which of the following could you do before subtracting the equations so that one variable will be eliminated when you add them?
4x+2y=7
3x-3y=15

anonymous · Answer

Multiply the top equation by 1/3.

       Multiply the top equation by 3 and the bottom equation by 4.

       Multiply the top equation by 15 and the bottom equation by 7.

       Multiply the top equation by -3 and the bottom equation by 2.

wolf1728 · Answer

Or subtract the second equation from the first

anonymous · Answer

i could but those are the given choices

anonymous · Answer

when i subtracted it i got x-y=-8... is that right?

wolf1728 · Answer

Yes that's right but I gave you the wrong advice on how to solve it.

anonymous · Answer

i tried multiplying the top by 3 and the bottom by 4...|dw:1378453540304:dw| so then solving it by subtraction would work