Triangle Angle Sum Theorem Proof

The Theorem states that the sum of all the three angles of a triangle is always equal to 180 degrees.

Triangle Angle Sum Theorem

Statement:   A triangle with the interior angles MNS. To prove: Diagram Construction: Proof: MN is a transversal. Similarly, --->(2) (is a straight line and sum of the angles at M is equal to 180. From (1) and (2), We get The measure of interior angles of a triangle or the two right angles are equal to 180 degrees.

The Theorem states that the sum of all the three angles of a triangle is always equal to 180 degrees.

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