## Geometry: Common Core (15th Edition)

$x = 45^{\circ}$
In this exercise, we are given the sides that are opposite and adjacent to an unknown angle. We can use the tangent ratio to find $x$, the unknown angle: tan $x = \frac{opposite}{adjacent}$ Let's plug in what we know: tan $x = \frac{6}{6}$ Take $tan^{-1}$ of the fraction to find the measure of $x$: $x = 45^{\circ}$