Question

1. angles abc and def are complementary angles. if m∠abc = 72°, what is m∠def? ∠def =

Explanation:

Step1: Recall complementary angles rule

Complementary angles sum to \(90^\circ\), so \(m\angle ABC + m\angle DEF = 90^\circ\).

Step2: Substitute known angle

Given \(m\angle ABC = 72^\circ\), solve for \(m\angle DEF\): \(m\angle DEF = 90^\circ - 72^\circ\).

Step3: Calculate the result

\(90 - 72 = 18\), so \(m\angle DEF = 18^\circ\).

Answer:

\(18^\circ\)