# Math Help - Help !

1. ## Help !

Hello,

I am trying to solve this equation:
7x + 3y = 12
3x + 7y = 6

If x and y satisfy the system of equations above, what is the value of x-y?

I have tried really hard to solve this, I am appalling bad at Math ! Any help would be appreciated..

2. ## Re: Help !

Using elimination, we could multiply the first equation by 3 and the second by -7 to get:

$21x+9y=36$

$-21x-49y=-42$

Now, add the equations to eliminate x, and then solve for y. Then plug in this value for y into either original equation to find x.

What do you find?

3. ## Re: Help !

easy way to find x-y in this question is just subtract 2nd equation from 1st and then divide the whole by 4
7x-3x+3y-7y=12-6
4x-4y=6
x-y=6/4
x-y=3/2

4. ## Re: Help !

LOL, I misread the question, I thought the OP was wanting to find (x,y), not x - y.

5. ## Re: Help !

Thanks guys !