Angle-Side Relationships in Triangles

The learner will write and solve equations using geometry concepts including the sum of the angles in a triangle, and angle relationships.

Angle/Triangle Relationships

Supplementary v. Complementary

Multiple Choice

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.

Multiple Choice

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

Multiple Choice

Find the missing angle.

• 60
• 70
• 50
• 140

Multiple Choice

Solve for x.

• G; x = 11.8

• G; x= 17

• G; x=80

• G; x= -1

Open Ended

What is the value of x?

Multiple Choice

Find the missing angle.

• 43
• 47
• 57
• 67

Multiple Choice

Are these angles complementary, supplementary or neither?

• complementary
• supplementary
• neither

Triangle- Interior Angles

The corners of a triangle could be cut and placed in a manner that would create a straight line.

Multiple Choice

Angles that are exactly 90 degrees are called _____ ______.

• tight angles
• acute angles
• obtuse angles
• right angles

Multiple Choice

The Triangle Sum Theorem states that the sum of all angles in a triangle is ______. 

• 45°
• 90°
• 180°
• 360°

Multiple Choice

Find the measure of the missing angle.

• 90^o
• 10⁰
• 130^o
• 50^o