SOLUTION: x^2-9=0

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Question 111372: x^2-9=0
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

x%5E2-9=0

%28x-3%29%28x%2B3%29=0 Factor the left side (note: if you need help with factoring, check out this solver)



Now set each factor equal to zero:

x-3=0 or x%2B3=0

x=3 or x=-3 Now solve for x in each case


So our solutions are x=3 or x=-3


Notice if we graph y=x%5E2-9 we get

+graph%28500%2C500%2C-10%2C10%2C-10%2C10%2C+x%5E2-9%29+

and we can see that the graph has roots at x=3 and x=-3, so this verifies our answer.