Answer
$10x^{10}$
Work Step by Step
We are given the expression $2x^{3}\times5x^{7}$. First, we can group like terms.
$(2\times5)\times(x^{3}\times x^{7})$
Next, we can use the product rule, which holds that $a^{m}\times{a^{n}}=a^{m+n}$ (where a is a real number, and m and n are positive integers).
$10\times(x^{3+7})=10x^{10}$