In a right triangle, if one of the acute angles measures $30°$, what is the measure of the other acute angle?

• A. $30°$
• B. $60°$
• C. $40°$
• D. $50°$

Answer: (B)

Verified step by step guidance

1. Recall that in a right triangle, the sum of the three interior angles is always 180 degrees.
2. Since one angle is a right angle, it measures 90 degrees.
3. Let the two acute angles be \( A \) and \( B \), and we know one of them is 30 degrees, so \( A = 30^\circ \).
4. Use the angle sum property: \( A + B + 90^\circ = 180^\circ \). Substitute \( A = 30^\circ \) to get \( 30^\circ + B + 90^\circ = 180^\circ \).
5. Solve for \( B \) by simplifying the equation: \( B = 180^\circ - 90^\circ - 30^\circ \).