Triangle Properties Practice

70° + 70° + ? = 180°

• 35°

• 70°

• 40°

• 140°

? + 90° + 50° = 180°

• 40°

• 50°

• 140°

• 180°

? + 52° + 87° = 180°

• 51°

• 46°

• 41°

• 31°

Which set of angles would NOT make a triangle (not 180°)? 

• 30°, 70° and 80° = ?

• 40°, 30° and 110° = ?

• 80°, 20° and 60 ° = ?

• 50°, 60 and 70° = ?

Will these side lengths form a triangle?

• yes

• no

Will these line segments form a triangle?

• yes

• no

Does a triangle with these
side lengths exist?
(Don't fall for this one.)
0, 11, 12

• Yes
• No
• I don't know.

side lengths of 4,4,4 form a triangle

• True
• False

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 34 and 2nd angle is 101?

• 32
• 39
• 45
• 54