Question

subtract. write your answer in simplest form. $-9\sqrt{7} - 3\sqrt{63}$

Explanation:

planation:

Step1: Simplify $\sqrt{63}$

$\sqrt{63} = \sqrt{9 \times 7} = 3\sqrt{7}$

Step2: Substitute back into expression

$-9\sqrt{7} - 3 \times 3\sqrt{7} = -9\sqrt{7} - 9\sqrt{7}$

Step3: Combine like terms

$-9\sqrt{7} - 9\sqrt{7} = -18\sqrt{7}$

Answer:

$-18\sqrt{7}$