Question

prove that the sum of the angle of a triangle is 180 degree​

Answer 1

Answer:

We know ,

[A + [B +[C =180°

60°+60°60°

180°

Answer 2

Answer:

Proved

Step-by-step explanation:

Given :

A triangle ABC.

To prove :

∠A+∠B+∠C=180  

⟹∠1+∠2+∠3=180  

 

Construction :

Through A, draw a line l parallel to BC.

Proof :

Since l∥BC. Therefore,

∠2=∠4  eq(i)

And, ∠3=∠5 eq(ii)

adding  eq(i)and(ii)

Therefore, ∠2+∠3=∠4+∠5

∠1+∠2+∠3=∠1+∠4+∠5  [adding∠1bothSide]

∠1+∠2+∠3=180  

 

Thus, the sum of three angles of a triangle is 180  

.