## Geometry: Common Core (15th Edition)

3$\sqrt 11$
The Pythagorean Theorem says that $(leg_{1}) ^{2}$+$(leg_{2})^{2}$=$hypotenuse^{2}$. This formula is more commonly referred to as $a^{2}$+$b^{2}$=$c^{2}$ You are given the lengths of one leg as 15 and the length of the hypotenuse as 18. Substitute 15 in for a and 18 in for c. $a^{2}$+$b^{2}$=$c^{2}$ $15^{2}$+$b^{2}$=$18^{2}$ 225+$b^{2}$=324 Subtract 225 from both sides $b^{2}$=99 Take the square root of both sides to find the length of the missing side b=3$\sqrt 11$