Question

Complete the statements to find the measurements of angle a and angle b ​

Answer 1

The measurement of angle a plus 120 must equal to 180 ( as angles on a straight line must equal to 180)
So measurement of angle a is 60 degrees
Measurement of angle b plus 60 plus 60 must equal to 180
So measurement of angle b is 60

Answer 2

m∠a + 120° = 180°

m∠a = 60°

m∠b + 60° + 60° = 180

m∠b = 60°