Class 9th math Review Exercise 1 solution english PCTB

\((vii)\) \(2^x\times 8^x = 64\) then \(x=\)

Option B : \(\frac{3}{2}\)

Explanation:

\[
\begin{align*}
2^x\times 8^x &= 64\\ 2^x\times 2^{3 \times x} &= 64\\ 2^x\times 2^{3x} &= 64\\2^{x+3x} &= 64\\2^{4x} &= 2^6
\end{align*}
\]

Equating exponents on both sides

\[
\begin{align*}
4x &=6\\x &=\frac{6}{4}\\&=\frac{3}{2}\\
\end{align*}
\]

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