Introduction to triangle angle sum theorem:

Triangle Angle Sum Theorem:

The Triangle angle sum theorem states that sum of all angles in a triangle equal to 180°.

Let A,B & C are the angles of a triangle

Then A + B + C = 180°

Example 1: Find the angle of C from the given figure.

Solution: We know that sum of all angles in a triangle = 180°

Let C be unknown angle. We know the angle of A = 50° & B = 48

By Triangle angle sum theorem, A + B + C = 180°

So, C + 50°+ 48° = 180°

C + 98º = 180°

C = 180° - 98 °

C = 82°

So the angle of C = 82°.

Example 2: Given angle A = 46, B = 52, C = 82. Proof that given triangle satisfies the Triangle angle sum theorem.

Solution: Here A = 46° & B = 52° & C = 82°

By Triangle angle sum theorem, A + B + C = 180°

So, 46° + 52°+ 82° = 180°

98°+ 82º = 180°

180° = 180°

Hence the given triangle satisfies the Triangle angle sum theorem