# Thread: [SOLVED] Help solving an equation

1. ## [SOLVED] Help solving an equation

I haven't done any algebra in years and I need to solve the following equation for x. Can anyone help me, or at least tell me how to go about it.

237.7y + xy - 7.5x = 0

2. Are you supposed to solve for "x=" in terms of y? Because you cannot solve this for a numerical value of x....

3. Yes, that is what I need.

4. Originally Posted by fantomx11
I haven't done any algebra in years and I need to solve the following equation for x. Can anyone help me, or at least tell me how to go about it.

237.7y + xy - 7.5x = 0
Hi there, if solving x in terms of y you need to isolate the terms that contain x on one side & factor the x out.

Here's one similar to your equation that I prepared earlier, model the steps from here and your's should be a piece of cake (hopefully chocolate cake)

$5y + xy -2x = 0$

leaving the x terms on the LHS

$xy -2x = -5y$

Factor out the x

$x(y -2) = -5y$

divide the other factor over to the RHS and bingo!

$x = \frac{-5y}{y-2}$

5. Oh, man I feel silly now. Factoring was the first thing I learned in algebra. Funny that I would forget that when the full formula was much more complex and I didn't really have a problem with that. Thanks for the refresh.

6. well. I feel obligated to put the final solution, now that you understand the problem :P

ok.

$xy-7.5x=-237.7y$

$x(y-7.5)=-237.7y$

$x=\frac{-237.7y}{y-7.5}$

well. there you go. Hope i didn't make a mistake

7. Shouldn't the solution be: $x=\frac{-237.7y}{y-7.5}$? Or did I get it wrong again.

8. Originally Posted by fantomx11
Shouldn't the solution be: $x=\frac{-237.7y}{y-7.5}$? Or did I get it wrong again.
Yes it is

9. Originally Posted by rtblue
$xy-7.5x=-237.7y$

$x(y-7.5)=237.7y$
The negative sign was not carried through.

10. yes, i'm sorry. i edited my post. I actually carried the negative on the first step, but i guess i forgot to write it on the following steps. Sorry.