Angle and Relationships

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 a linear pair of angles?

Back

A linear pair of angles are two adjacent angles that form a straight line, meaning their measures add up to 180 degrees.

Front

What is the sum of angles in a triangle?

Back

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

Front

What is the measure of a right angle?

Back

A right angle measures 90 degrees.

Front

What are complementary angles?

Back

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

Front

What are supplementary angles?

Back

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

Front

How do you find the measure of an angle in a linear pair?

Back

To find the measure of an angle in a linear pair, subtract the measure of the other angle from 180 degrees.

Front

If m∠A = 25°, what is m∠B if ∠A and ∠B are complementary?

Back

m∠B = 65° (since 90° - 25° = 65°).

Front

What is the relationship between vertical angles?

Back

Vertical angles are equal; they are the angles opposite each other when two lines intersect.

Front

If m∠1 = (5x + 9)° and m∠2 = (3x + 11)°, what is the equation to find x if they form a linear pair?

Back

Set up the equation: (5x + 9) + (3x + 11) = 180.