Chapter 3 Test Angles and Triangles

Front

What is an angle?

Back

An angle is formed by two rays (sides of the angle) that share a common endpoint (the vertex).

Front

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

Back

The sum of the interior angles of a triangle is always 180 degrees.

Front

What does it mean for two triangles to be similar?

Back

Two triangles are similar if their corresponding angles are equal and their corresponding sides are in proportion.

Front

How do you find the measure of a missing angle in a triangle?

Back

To find the measure of a missing angle in a triangle, subtract the sum of the known angles from 180 degrees.

Front

What is the definition of complementary angles?

Back

Complementary angles are two angles whose measures add up to 90 degrees.

Front

What is the definition of supplementary angles?

Back

Supplementary angles are two angles whose measures add up to 180 degrees.

Front

If one angle measures 47 degrees, what is the measure of its complementary angle?

Back

The complementary angle measures 43 degrees (90 - 47 = 43).

Front

If two angles are supplementary and one measures 98 degrees, what is the measure of the other angle?

Back

The other angle measures 82 degrees (180 - 98 = 82).

Front

What is the definition of an isosceles triangle?

Back

An isosceles triangle is a triangle that has at least two sides of equal length.

Front

What is the definition of an equilateral triangle?

Back

An equilateral triangle is a triangle in which all three sides are of equal length and all three angles are equal (each measuring 60 degrees).