Factor $99=3^{2}\times 11$. Rewrite the square root of the product $\sqrt{3^{2}\times 11}$ as the product of square roots $\sqrt{3^{2}}\sqrt{11}$. Take the square root of $3^{2}$.
$$3\times 3\sqrt{11}-5\sqrt{44}-3\sqrt{11}$$
Multiply $3$ and $3$ to get $9$.
$$9\sqrt{11}-5\sqrt{44}-3\sqrt{11}$$
Factor $44=2^{2}\times 11$. Rewrite the square root of the product $\sqrt{2^{2}\times 11}$ as the product of square roots $\sqrt{2^{2}}\sqrt{11}$. Take the square root of $2^{2}$.
$$9\sqrt{11}-5\times 2\sqrt{11}-3\sqrt{11}$$
Multiply $-5$ and $2$ to get $-10$.
$$9\sqrt{11}-10\sqrt{11}-3\sqrt{11}$$
Combine $9\sqrt{11}$ and $-10\sqrt{11}$ to get $-\sqrt{11}$.
$$-\sqrt{11}-3\sqrt{11}$$
Combine $-\sqrt{11}$ and $-3\sqrt{11}$ to get $-4\sqrt{11}$.
