Question

\(\left\{{}\begin{matrix}2a+4b=3\\a-8b=9\end{matrix}\right.\)

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Answer 1

\(\Leftrightarrow\left\{{}\begin{matrix}4a+8b=6\\a-8b=9\end{matrix}\right.\)

\(\Leftrightarrow\left\{{}\begin{matrix}5a=15\\b=\dfrac{a-9}{8}\end{matrix}\right.\)

\(\Leftrightarrow\left\{{}\begin{matrix}a=3\\b=-\dfrac{3}{4}\end{matrix}\right.\)