SOLUTION: Solve 36⋅x2 - 81 = 0 by using square roots.

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Question 637696: Solve 36⋅x2 - 81 = 0 by using square roots.
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
36x%5E2-81=0...both sides divide by 9
36x%5E2%2F9-81%2F9=0%2F9
4x%5E2-9=0
%282x%29%5E2-3%5E2=0
%282x-3%29%282x%2B3%29=0

solutions:
%282x-3%29=0......->..2x=3....->..x=3%2F2
and
%282x%2B3%29=0......->..2x=-3....->..x=-3%2F2