Question

Q3) Prove that the sum of the angles of a triangle is 180º. Using this
result, find x(refer fig 1)
(3 marta)
ÁÁ
REA​

Answer 1

Step-by-step explanation:

Given :

A triangle ABC.

To prove :

∠A+∠B+∠C=180

o

⟹∠1+∠2+∠3=180

o

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

o

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

o

.

Answer 2

Answer:

hope it will help you⬇️⬇️⬇️⬇️⬇️⬇️⬇️

In order to prove that the sum of angles of a triangle is 180, you must know the theorems of angles of a triangle. We know that, alternate interior angles are of equal magnitude. This'll help us get the answer. Let us assume a triangle ABC.Feb 9, 2018