SOLUTION: x^2-1=8 solve using square roots

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Question 451671: x^2-1=8 solve using square roots
Answer by pedjajov(51) About Me  (Show Source):
You can put this solution on YOUR website!
This can be written as

x%5E2-1-8=0
x%5E2-9=0, this is now difference of two squared numbers, x and 3
x%5E2-3%5E2=0, this is product of sum and differnce x and 3
%28x%2B3%29%28x-3%29=0

So it can be

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

We say roots of this quadratic equation are 3 and -3.