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2 years ago

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How to solve this equation

1 answer:

mariarad [96]2 years ago

7 0

$\bf \sqrt{5x+19}-4=3x-15
\\\\
\sqrt{5x+19}=3x-15+4\\\\ \sqrt{5x+19}=3x-11\leftarrow \textit{square both sides}
\\\\
(\sqrt{5x+19})^2=(3x-11)^2
\\\\
5x+19=(3x-11)^2\qquad 
\begin{cases}
(3x-11)^2\to (3x-11)(3x-11)\\
 --------------\\
\textit{or use FOIL to expand it}
\end{cases}$

then solve for "x"

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