# Can someone help with sqrt(x-3)+sqrt(x+2)=5

• Jun 30th 2008, 09:57 AM
chiques
Can someone help with sqrt(x-3)+sqrt(x+2)=5
I know there are other ways to solve this, but if I keep to the rules of Algebra I should be able to solve it this way. Can anyone give me any insight on what I'm doing wrong???(Worried)

I know the answer is X=7 but 99.99% of true exams require work to prove it.

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• Jun 30th 2008, 10:00 AM
o_O
There's an error in going from your second to third step: $-3 + 2 = {\color{blue}-}1$ (not +1).

Also, make sure you change the sign when moving a term over to the other side of the equal sign. In your third last step, that should be a +4x^2 (not -).
• Jun 30th 2008, 10:08 AM
kalyanram
Hi,
The actual problem is $(a+b)^2 = a^2 + 2ab + b^2$
you missed out the "2" in 2ab term if you include that in your second step
$x^2$ cancels out in your fourth step giving you x=7, when you solve the linear equation.

~Kalyan.
• Jun 30th 2008, 01:12 PM
chiques
You guys rock!
It's these little typos and forgetful things with these kind of problems that always kill me. With your help I was able to refresh my memory.
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I appreciate everyones assistance. (Clapping)(Clapping)(Clapping)