## Geometry: Common Core (15th Edition)

$C$
In this exercise, the height of the building is the side opposite to the unknown angle, and the shadow is the side adjacent to the angle. We can use the tangent ratio to find $x$, the angle of elevation: tan $x = \frac{opposite}{adjacent}$ Let's plug in what we know: tan $x = \frac{107}{90}$ Take $tan^{-1}$ of the fraction to find the measure of $x$: $x = 50^{\circ}$ The answer is option $C$.