#### Answer

$-30\sqrt{30}$

#### Work Step by Step

First of all, in order to make this one large square root, we multiply the coefficients to obtain that the new coefficient is -30. Also, recall, $\sqrt{a}\times \sqrt{b}= \sqrt{a \times b}$. Thus, we can multiply 3 and 10 to obtain the simplified expression:
$-30\sqrt{3 \times 10}=-30\sqrt{30}$