Answer
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Work Step by Step
Based on the product rule for exponents, we know that $a^{m}\times a^{n}=a^{m+n}$ (where $m$ and $n$ are positive integers and $a$ is a real number).
Therefore, to simplify $x^{2}\times x^{7}$, keep the base and add the exponents.
$x^{2}\times x^{7}=x^{2+7}=x^{9}$