one angle of a right triangle measures 18°. what is the measure of the other acute angle?

Explanation:

Step1: Recall triangle angle sum

The sum of angles in a triangle is $180^\circ$. A right triangle has one $90^\circ$ angle.

Step2: Set up equation for unknown angle

Let the unknown acute angle be $x$. Then $90^\circ + 18^\circ + x = 180^\circ$.

Step3: Solve for the unknown angle

Calculate $x = 180^\circ - 90^\circ - 18^\circ$

Answer:

$72^\circ$