Answer
$10{x^{4}}\sqrt {2x}$
Work Step by Step
$\sqrt {200x^{9}}$
=$\sqrt {2\times100\times x^{8}\times x}$
=$\sqrt {2}\times \sqrt {100}\times \sqrt {x^{8}}\times \sqrt {x}$
=$\sqrt {2}\times 10\times {x^{4}}\times \sqrt {x}$
=$10\times {x^{4}}\times \sqrt {x}\times \sqrt {2}$
=$10{x^{4}}\times \sqrt {2x}$
=$10{x^{4}}\sqrt {2x}$
