Answer:
Explanation:
given :
y = 120 degree
z = 57 degree
angle x = ?
first lets find angle c in triangle BDC
angle c + z = y (sum of two interior opposite angle is equal to the exterior angle formed)
angle C + 57 = 120
angle C = 120 -57
angle C = 63 degree
Now lets find angle B in triangle BDC
angle B + angle C + z = 180 degree (sum of interior angles of a triangle)
angle B + 63 + 57 = 180
angle B + 120 = 180
angle B = 180 - 120
angle B = 60 degree
now for angle x
angle B + z = angle x (sum of two interior opposite angles is equal to the exterior angle formed)
60 + 57 = x
117 = x