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Solve x^2+ 14× = 80 by completing the square. If there are multiple answers, list them separated by a comma (e.g.,1,2) Note: If there is no solution, enter Ø.

1 Answer

7 votes

We have the following:


x^2+14x=80

solving:


\begin{gathered} x^2+14x+7^2=80+7^2 \\ (x+7)^2=129 \\ x+7=\pm\sqrt[]{129} \\ x=\sqrt[]{129}-7 \\ x=-\sqrt[]{129}-7 \end{gathered}

User Sebastian Kuhn
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