## Introductory Algebra for College Students (7th Edition)

$15\sqrt{3}-9\sqrt{2}$
Simplify the radicals that can still be simplified by factoring the radicand so that one of the factors is a perfect square: $=5\sqrt{9(3)}-3\sqrt{9(2)} \\=5\sqrt{3^2(3)} -3\sqrt{3^2(2)} \\=5\cdot 3\sqrt{3} -3\cdot 3\sqrt{2} \\=15\sqrt{3}-9\sqrt{2}$