Hi, I am getting frustrated with trying to solve this equation:(adsbygoogle = window.adsbygoogle || []).push({});

sqrt(x+9) - sqrt(x-6) = 3.

I know that the answer is x=7 because of guess and check. I don't know how to show it algebraically. Squaring both sides will cancel out the x. Is there a trick or something this? Please help. Thanks in advance.

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# Solving for X involving Square Roots

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