Introductory Algebra for College Students (7th Edition)

$3((3x)^{2}+5^{2})$
$27x^{2}+75\qquad$...factor out the common term, $3$ $=3(9x^{2}+25)$ A sum of two squares cannot be further factored. $=3((3x)^{2}+5^{2})$