9514 1404 393
Answer:
135°
Explanation:
In order to answer the question, we must assume that the black lines are parallel to each other.
The given angles (2, 8) are "same-side (consecutive) exterior" angles, so are supplementary.
∠2 +∠8 = 180°
15x +5x = 180°
x = 180°/20 = 9°
∠2 = 15x = 15(9°) = 135°
Angles 2 and 3 are vertical angles, so angle 3 has the same measure as angle 2.
∠3 = 135°