Use the Triangle Angle Sum Theorem to find the measure of the third angle if the first and second angle measure 63° and 40°

Answer 1

The Triangle Angle Sum Theorem states that the sum of the measures of the three angles in a triangle is always 180°.

Let's represent the three angles as a, b, and c.

Given that a = 63° and b = 40°, we need to find c.

Using the Triangle Angle Sum Theorem, we can write:

a + b + c = 180°

Substituting the given values, we get:

63° + 40° + c = 180°

Combining like terms:

103° + c = 180°

To isolate c, we can subtract 103° from both sides:

c = 180° - 103°

Simplifying the right side:

c = 77°

Therefore, the measure of the third angle is 77°.