some of the angles of a triangle is 180 degree. solve it
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some of the angles of a triangle is 180 degree. solve it
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ANSWER
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
.this proved....
i hope it's helps you