Question

please give the answer​

Answer 1

Answer:

lets suppose the triangle as ∆ABC

<a +<b+<c = 180° [by theorem 7.1]

there are three angles = a ,b, and c

so, we can write 3a+b+c =180°

therefore, a+b+c = 180°/3

therefore , a+b+c = 60°

hence proved