Solve by elimination:
4x-y=-5
-2x+3y=10

Question

Solve by elimination: 
4x-y=-5
-2x+3y=10

thatonegirl_ · Answer

To solve by elimination, you need to have one equation with a negative coefficient (and same variable) along with the other equation but with the positive coefficient (and same variable). To get the same coefficients, you need to multiply the entire equation by a number so it is equal to the other equations coefficient.

anonymous · Answer

Okay so if I multiply the top one by 3 would that work?

thatonegirl_ · Answer

So in the first equation there is a 4x, and the second one there is a -2, so you could multiply (-2x+3y=10)*2 so that you get -4x-12y=40.

thatonegirl_ · Answer

or ya u can do the y too if u want u would multiply it all by 3 like u said

thatonegirl_ · Answer

Do you know what to do after that?

anonymous · Answer

but… when I do that i end up getting -6x=-15 and that is really weird.

anonymous · Answer

Oh… never mind I figured out what I was doing wrong! Thanks for you help!

thatonegirl_ · Answer

yea no prob! Did u end up getting x=-1/2?

anonymous · Answer

Yes.

thatonegirl_ · Answer

okay cool, then u just plug it into either of the equations to find y :)

anonymous · Answer

Okay, thanks again!

thatonegirl_ · Answer

You're welcome!