## Geometry: Common Core (15th Edition)

$x = \sqrt {170}$
We can find the third side by using the Pythagorean theorem, which states that $a^2 + b^2 = c^2$, where $a$ and $b$ are the legs of the right triangle and $c$ is the hypotenuse. Let's plug in what we know into the Pythagorean theorem: $7^2 + 11^2 = x^2$ Evaluate the exponents: $49 + 121 = x^2$ Add to simplify: $170 = x^2$ Take the positive square root to solve for $x$: $x = \sqrt {170}$