Answer:
m∠3 = 63°
Step-by-step explanation:
Linear pair: If in adjacent angles, the non common arms form a line, then they are called linear pair.
∠1 + ∠5 = 180 {linear pair}
117 + ∠5 = 180
∠5= 180 - 117
∠5 = 63°
If l₁ // l₂, then alternate interior angles should be congruent.
∠3 = ∠5
∠3 = 63°
