Geometry - Protractors - 4th grade

Front

What is a protractor?

Back

A protractor is a tool used to measure angles in degrees.

Front

How many degrees are in a full circle?

Back

360 degrees.

Front

What is the measurement of a right angle?

Back

90 degrees.

Front

If angle A measures 50° and angle B measures 40°, what is the measurement of angle C if they are complementary?

Back

Angle C measures 90° - (50° + 40°) = 0°.

Front

What is the sum of the angles in a triangle?

Back

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

Front

If one angle in a triangle measures 60° and another measures 70°, what is the measure of the third angle?

Back

The third angle measures 180° - (60° + 70°) = 50°.

Front

What is an acute angle?

Back

An acute angle is an angle that measures less than 90 degrees.

Front

What is an obtuse angle?

Back

An obtuse angle is an angle that measures more than 90 degrees but less than 180 degrees.

Front

What is a straight angle?

Back

A straight angle measures exactly 180 degrees.

Front

If angle LMO measures 128° and angle LMN is a right angle, what is the measure of angle NMO?

Back

Angle NMO measures 38°.