1. Solve the triangle.
AABC, given ZB = 57°, ZC = 720,
and b = 18 m.

Answer:
Angle A= 61°
Step-by-step explanation:
angle A+ Angle B+Angle C= 180°( Angle sum property)
∠A+57+72= 180°
∠A= 180°- 127°= 61°