Fundamental Identities and Complementary Angles

What are complementary angles?

• Angles that add up to 180°
• Angles that add up to 90°
• Angles that are equal to each other
• Angles that are opposite of each other when lines intersect.

Are these angles an example of complementary, supplementary, or neither?

• Complementary
• Supplementary
• Neither

Are these angles an example of complementary, supplementary, or neither?

• Complementary
• Supplementary
• Neither

What are supplementary angles?

• Angles that add up to 180°
• Angles that add up to 90°
• Angles that are equal to each other
• Angles that are opposite of each other when lines intersect

These angles are...

• Complementary
• Supplementary
• Neither

Are these angles an example of complementary, supplementary, or neither?

• Complementary
• Supplementary
• Neither

These angles are...

• Complementary
• Supplementary
• Neither

Find the missing angle.

• 60
• 70
• 50
• 140

What is the measure of the missing angle?

• 39
• 129
• 119
• 129

If ∠C and ∠D are supplementary, and the measure of ∠D is 45°, what is the measure of ∠C?

• 135
• 45
• 125
• 90