9. Roots and Radicals

Add or subtract as indicated and simplify.

$2\sqrt{5}+6\sqrt{5}$

Add or subtract as indicated and simplify.

$\sqrt{12}+\sqrt{20}-\sqrt{45}$

Add or subtract as indicated and simplify.

$\sqrt[3]{50}+\sqrt[3]{8}-\sqrt[3]{18}$

Add or subtract as indicated and simplify.

$6\sqrt[4]{3y}+2\sqrt[4]{3y}-5\sqrt[4]{3y}$

True or False:

$\sqrt{9+16}$ and $\sqrt{9}+\sqrt{16}$ are equal.