SOLUTION: I need to solve this by factoring: {{{ x^2-9=0 }}}

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Question 328254: I need to solve this by factoring: +x%5E2-9=0+
Answer by meay7c(10) About Me  (Show Source):
You can put this solution on YOUR website!
The first step is to isolate x.
x%5E2+-+9+=+0
Add 9 to both sides yielding:

x%5E2+-+9+%2B+9+=+0+%2B+9
Simplify:
x%5E2+=+9
To undo the squaring operation we must take the square root of x and take the square root of 9 as well.
sqrt+%28x%5E2%29+=+%22%2B+or+-%22+sqrt+%289%29
Now we have:
x+=+%22%2B+or+-%22+sqrt+%289%29
x = + or - 3.
Check our solutions by plugging our x values into the original equation:
x%5E2+-+9+=+0
Where x = 3
%283%29%5E2+-+9+=+0
9 - 9 = 0 Yes!!!
and
Where x = -3
%28-3%29%5E2+-+9+=+0
*Remember any negative number squared yields a positive answer.
9 - 9 = 0 Yes!!!
Good Luck :-)