Question

Calculate the unknown marked angles in each figure:- ​

Answer 1

Step-by-step explanation:

80+20+y=180. (angle sum property of a triangle)

100+y=180

y=180-100

y=80°

Answer 2

Answer:

80

Step-by-step explanation:

Sun of the angles in a triangle are 180.

i.e. 80+20+y=180

100+y=180

y=180-100

y=80

Therefore unknown marked angle y is 80°