Answer
The unknown angle is 32$^{\circ}$
Work Step by Step
The sum of the angle in a Triangle is 180$^{\circ}$.
Here we will solve for the unknown angle. We will label it $X$.
Therefore:
180$^{\circ}$ = 90$^{\circ}$ + 58$^{\circ}$ + $X$
$X$ = 180$^{\circ}$ - (90$^{\circ}$ + 58$^{\circ}$)
$X$ = 180$^{\circ}$ - (148$^{\circ}$)
$X$ = 32$^{\circ}$
