All About Triangles

What is the missing angle?

• 90°

• 87°

• 80°

• 88°

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

• 80

• 100

• 60

• 90

Which set of side lengths will make a triangle?

• 6, 8, 13

• 7, 9, 18

• 7, 7, 14

• 2, 6, 9

A triangle has angle measurements of 54°, 52°, and 74°. What kind of triangle is it?

• acute triangle

• right triangle

• obtuse triangle

• none of the above

Which of these lengths CANNOT represent the sides of a triangle?

• 32, 34, 60

• 28, 30, 58

• 13, 20, 27

• 2, 4, 5

How many triangles exist with the given side lengths?
7 in, 7 in, 7 in

• No triangle exists with the given side lengths.

• More than one unique triangle exists with the given side lengths. 

• Exactly one unique triangle exists with the given side lengths.

Two sides of a triangle have side lengths of 17 meters and 12 meters.  What is the range of possible lengths for the third side?

• 12 < x < 17

• 12 < x < 29

• 5 < x < 17

• 5 < x < 29

Two sides of a triangle are 14 cm and 19 cm.  What is a possible length for the third side?

• 5 cm

• 11 cm

• 33 cm

• 40 cm

How many triangles exist with the given angle measures?  55°, 45°, 90°

• No triangle exists

• Exactly one unique triangle exists

• More than one triangle exists

Does a triangle with these side lengths exist?
33, 16, 17

• Yes

• No

• I don't know.