How do you solve x+2y=5 and 2x-3y=-4?

1 Answer
Nov 4, 2015

x = 1
y = 2

Explanation:

Ok. So prefer the elimination method, but you can do this with substitution as well.

First put the equations on top of each other

x +2y= 5
2x-3y=-4

Then find the variable that would be easiest to cancel out. I think it's x because you only have to modify one of the equations. Let's multiply the first equation by -2. This will allow us to cancel out the two x's in the equations.

-2x - 4y = -10
2x - 3y = -4

Now let's add the two equations together!

0x-7y = -14

or just

-7y = -14

Now we simply divide by -7 to get y

y = 2

But wait! We're not done!

Plug y back into one of two equations to get x. I'll use the first equation again.

x + 2(2) = 5

which simplifies to

x + 4 = 5

So we subtract 4 from both sides, and get

x = 1

Hope this helps!