Factor $80=4^{2}\times 5$. Rewrite the square root of the product $\sqrt{4^{2}\times 5}$ as the product of square roots $\sqrt{4^{2}}\sqrt{5}$. Take the square root of $4^{2}$.
Factor $125=5^{2}\times 5$. Rewrite the square root of the product $\sqrt{5^{2}\times 5}$ as the product of square roots $\sqrt{5^{2}}\sqrt{5}$. Take the square root of $5^{2}$.
Factor $45=3^{2}\times 5$. Rewrite the square root of the product $\sqrt{3^{2}\times 5}$ as the product of square roots $\sqrt{3^{2}}\sqrt{5}$. Take the square root of $3^{2}$.
