Question

Answer 1

\(2x\left(x-3\right)+5\left(x-3\right)=0\\ \Leftrightarrow\left(x-3\right)\left(2x+5\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x-3=0\\2x+5=0\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=3\\2x=-5\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=3\\x=-\dfrac{5}{2}\end{matrix}\right.\)

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