Triangle Concepts

What is the sum of the interior angles of a triangle?

• 360

• 270

• 180

• 90

If one angle of a triangle measures 60 degrees and another angle measures 40 degrees, what is the measure of the third angle?

• 90

• 50

• 70

• 80

If the measure of one angle of a triangle is 90 degrees and another angle measures 45 degrees, what is the measure of the third angle?

• 90

• 30

• 60

• 45

If one exterior angle of a triangle measures 120 degrees, what is the measure of the interior angle adjacent to it?

• 90

• 30

• 120

• 60

If one exterior angle of a triangle measures 150 degrees, what is the measure of the other two interior angles?

• 60 degrees

• 45 degrees

• 30 degrees

• 75 degrees

What are similar triangles?

• Triangles that have the same size and shape.

• Triangles that have the same size but not necessarily the same shape.

• Triangles that have different shapes and sizes.

• Triangles that have the same shape but not necessarily the same size.

If two triangles have the same shape but different sizes, are they similar?

• No

• Maybe

• Yes

• Not necessarily

If two triangles have proportional side lengths, are they similar?

• Yes

• No

• Sometimes

• Not necessarily

If two triangles have congruent corresponding angles, are they similar?

• No

• Yes.

• Sometimes.

• It depends.

Find the value of k.

(a)