Answer:
72°
Step-by-step explanation:
Para el pentagono ABCDE,
m<C = (n - 2)(180)/n = (3)(180)/5 = 108
m<D = m<C = 108
Para el quadrilatero BCDE,
m<CBE + m<C + m<D + m<DEB = (n - 2)180 = 2(180) = 360
m<C = m<D = 108
m<CBE = m<DEB = x
m<CBE + m<C + m<D + m<DEB = 360
x + 108 + 108 + x = 360
2x + 216 = 360
x + 108 = 180
x = 72
