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26 votes
Solve by completing the square and using square roots 6x^2-6=90

User Matt Bryson
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1 Answer

28 votes
28 votes

In this equation we can't complete the square (cause there's no linear term) but we can solve it, so let's do that:


\begin{gathered} 6x^2-6=90 \\ 6x^2=96 \\ x^2=(96)/(6) \\ x^2=16 \\ x=\pm\sqrt[]{16} \\ x=\pm4 \end{gathered}

Therefore x=4 or x=-4.

User Michael Garrison
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