Angle Relationships, Complementary, Supplementary, Triangle Sum Theorem

The sum of the angle measures of a triangle is 180° 
m∠A + m∠B + m∠C = 180°

• Triangle Sum Theorem

• Exterior Angle Theorem

• Third Angle Theorem

• Centroid Theorem

The acute angles of a right triangle are

• supplementary

• linear

• complementary

• 60°

The measure of each angle of an equiangular triangle is 

• complementary

• supplementary

• 60°

• 45°

The measure of an exterior angle of a triangle is equal to the sum of the measures of its remote interior angles.
m∠4 = m∠1 + m∠2

• Triangle Sum Theorem

• Exterior Angle Theorem

• Third Angles Theorem

• Congruent Triangles Theorem

Set up an equation that will help you solve for x.

• 60 + 75 + 180 = x

• 60 + 75 + x = 180

• 60 + 75 = x

• 60 + x = 75

Q1. What is the sum of 10 and 7?

• 1) 10

• A) 17

• 2) 80

• 3) 90

What is the measure of x?

• 101°

• 111°

• 121°

• 131°

• A

• B

• C

• D

Q1. What is the sum of 20 and 23?

• 1) 23

• A) 20

• 2) 44

• C) 16

• 25
• 35
• 45
• 55