Answer:
m∠3 = 49°
Explanation:
From the picture attached,
lines m and n are the parallel lines and line t is a transversal line intersecting these parallel lines at E and B respectively.
Therefore, ∠DEF ≅ ∠ABC [Exterior alternate angles]
m∠1 + m∠2 = m∠4 + m∠5
m∠4 = m∠5 [line s bisects ∠ABC]
50° + 48° = m∠4 + m∠4
98° = 2m∠4
m∠4 = 49°
Since, ∠4 ≅ ∠3 [Vertically opposite angles]
m∠3 = 49°