## Intermediate Algebra (6th Edition)

Because the tower forms a 90-degree angle, we use the Pythagorean Theorem, $a^{2}+b^{2}=c^{2}$. We are given the length of two sides, $a$ and $b$. $a=45$ feet and $b=60$ feet. $45^{2}+60^{2}=c^{2}$ Now we must solve for $c^{2}$. Evaluate the exponents: $2025+3600=5625$ $5625=c^{2}$ Solve for $c^{2}$. $\sqrt 5625 =75$ $75^{2}=5625$ $45^{2}+60^{2}=75^{2}$ Because $c=75$, the length of the cable is $75$ ft.