In a right triangle, one angle is always \(90^\circ\). If one of the other angles is \(58^\circ\), you can find the measure of the third angle by using the fact that the sum of the angles in any triangle is \(180^\circ\).
So, the measure of the third angle \(C\) can be calculated as follows:
\[ C = 180^\circ - 90^\circ - 58^\circ \]
\[ C = 180^\circ - 148^\circ = 32^\circ \]
Therefore, the measure of the third angle is \(32^\circ\).