Respuesta :
Answer:
see explanation
Step-by-step explanation:
Since there are 3 parallel lines, then
a and 31° are corresponding angles and congruent, thus
a = 31°
b and 31° are same- side interior angles and supplementary, thus
b = 180° - 31° = 149°
c and b are vertical angles and congruent, thus
c = 149°
d and 31° are alternate angles and congruent, thus
d = 31°
a = 31°, b = 149°, c = 149°, d = 31°