Question

angle 3 is 120°. what is the measure of ∠5? m∠5 = ?° answer in degrees.

Explanation:

Step1: Identify relationship between ∠3 and ∠4

∠3 and ∠4 are supplementary (linear pair), so \( m\angle4 = 180^\circ - m\angle3 \).
\( m\angle4 = 180^\circ - 120^\circ = 60^\circ \).

Step2: Identify relationship between ∠4 and ∠5

∠4 and ∠5 are alternate interior angles (since lines are parallel, cut by transversal), so \( m\angle5 = m\angle4 \).
\( m\angle5 = 60^\circ \).

Answer:

60