# Math Help - Don't know how to solve this one

1. ## Don't know how to solve this one

While working on some physics exercises today, I got stuck on an algebra problem. A simplified version would look something like this:

$x^2+x\sqrt(x^2-10)=5$

Anyone have a neat little trick for this type of problem?

2. Originally Posted by TwoPlusTwo
While working on some physics exercises today, I got stuck on an algebra problem. A simplified version would look something like this:

$x^2+x\sqrt(x^2-10)=5$

Anyone have a neat little trick for this type of problem?
Write it as:

$x\sqrt(x^2-10)=5-x^2$

And then square both sides.

3. Subtract [tex]x^2[tex] from both sides to give $x\sqrt{x^2-10} = 5-x^2$

You can now square both sides but check for extraneous solutions by subbing back into your equation. Also note that $x^2-10 \geq 0$

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