Question

4. The exterior angles obtained on producing the base of a triangle both ways are 100 and 120. Find all the angles.

Answer 1

linear pair of triangle apply this so we find

angle B= 180-100=80

angle C=180-120=60

apply angle sum property =A+B+C=180

80+60+A= 180

A=40

Answer 2

Answer:

Step-by-step explanation:

2 + 3 = 100 (exterior angle property)

1 + 100 = 180 (Linear pair)

1 = 80

1 + 2 = 120 (exterior angle property)

80 + 2 = 120

2 = 40

1 + 2 + 3 = 180 (Angle sum property of )

80 + 40 + 3 = 180

3 = 60

Hence, 1 = 80, 2= 40, 3 = 60