## Thinking Mathematically (6th Edition)

$5\sqrt{2}$
RECALL: For non-negative numbers a and b, $\sqrt{a} \cdot \sqrt{b} = \sqrt{ab}$ Use the rule above to obtain: $=\sqrt{10(5)} \\=\sqrt{50}$ Factor the radicand so that one of the factors is a perfect square. $=\sqrt{25(2)} \\=\sqrt{5^2(2)}$ Simplify to obtain: $=5\sqrt{2}$