Answer
$6\sqrt5$
Work Step by Step
$\sqrt{10}\times\sqrt{18}\longrightarrow$ factor the radicands
=$\sqrt{5\times2}\times\sqrt{2\times9}\longrightarrow$ multiplication property of square roots
=$\sqrt{5}\times\sqrt{2}\times\sqrt{2}\times\sqrt{9}\longrightarrow$ simplify
=$\sqrt5\times2\times3\longrightarrow$ simplify
=$6\sqrt5$
