If a right triangle has one angle measuring $30°$, what is the measure of the other non-right angle?

• A. $60°$
• B. $120°$
• C. $159°$
• D. $21°$

Answer: (A)

Verified step by step guidance

1. Recall that the sum of the interior angles in any triangle is always \$180^\circ$.
2. In a right triangle, one angle is always \$90^\circ$ by definition.
3. Given one of the other angles is \$30^\circ\(, set up the equation for the sum of angles: \)90^\circ + 30^\circ + \text{other angle} = 180^\circ$.
4. Solve for the other angle by subtracting the sum of the known angles from \$180^\circ\(: \)\text{other angle} = 180^\circ - 90^\circ - 30^\circ$.
5. Calculate the value of the other angle to find its measure.