Triangles

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

• 45°
• 90°
• 180°
• 360°

What is the third angle of a triangle whose 1st angle is 79 and the 2nd angle is 43?

• 43
• 58
• 72
• 101

If 2 of the angles of a triangle are 30 and 70 degrees, the third angle measures...

• 80
• 100
• 60
• 90

Find the measure of the indicated angle. 

• 26
• 36
• 85
• 144

A student is trying to construct triangles using four different sets of angles. The angles in each set are given below. Which set will form a triangle?

• 45°, 65°, 70°

• 150°, 110°, 100°

• 50°, 50°, 50°

• 90°, 90°, 90°

Which of the following is false?

• A triangle can be drawn with 3 acute angles.

• A triangle can be drawn with 2 obtuse and one acute angles.

• A triangle can be drawn with only one obtuse angle and two acute angles.

• A triangle can be drawn with only one right angle and two acute angles.

A student is trying to construct triangles using four different sets of angles. The angles in each set are given below. Which set will form a triangle?

• 45°, 65°, 70°

• 150°, 110°, 100°

• 50°, 50°, 50°

• 90°, 90°, 90°

Will these three sides form a triangle?

• yes

• no

Will these side lengths form a triangle?

• yes

• no

Will these line segments form a triangle?

• yes

• no