Question

the sum of the angles of a truangle is 180.

Answer 1

yes , the sum of all the angles of a triangle is 180°

hope it helps you ☺✌✌

Answer 2

Let us take a triangle PQR. so we need to prove that...

Angle PQR+angle QPR+angle PRQ=180°

CONSTRUCTION: Let us draw a line XPY parallel to QR through the opposite vertex P.

PROOF: Since XPY is a line,

Therefore,

Angle XPQ+Angle QPR+angle RPY=180°

____(1)

But XPY || QR & PQ, PR are transversals.

So, angle XPQ=Angle PQR

& Angle RPY=Angle PRQ

(Because these are alternate interior angles)

Substituting angle XPQ & Angle RPY in (1), we get...

Angle PQR+angle QPR+angle PRQ=180°

HOPE IT HELPS

Thanking you

Yours truly

ZunayedTIME

(SRK Fan)