Question

d) (2x - 3)\(^2\) - 49 = 0

Answer 1

\(\left(2x-3\right)^2-49=0\)

\(\Leftrightarrow\left(2x-3\right)^2-7^2=0\)

\(\Leftrightarrow\left(2x-3-7\right)\left(2x-3+7\right)=0\)

\(\Leftrightarrow\left(2x-10\right)\left(2x+4\right)=0\)

\(\Leftrightarrow4\left(x-5\right)\left(x+2\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x-5=0\\x+2=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=5\\x=-2\end{matrix}\right.\)

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