Angles Flashcard

Front

∠1 and ∠3 can best be described as (opposite angles formed by intersecting lines).

Back

vertical angles

Answer explanation

∠1 and ∠3 are vertical angles because they are opposite angles formed by intersecting lines. Vertical angles are always equal, distinguishing them from complementary, supplementary, and adjacent angles.

Front

Two angles are supplementary if the sum (adding them together) of their angles is 180^o.

Back

True

Answer explanation

The statement is true because supplementary angles are defined as two angles whose measures add up to 180 degrees. Therefore, the correct answer is True.

Front

What is the measurement of a right angle?

Back

90 degrees

Answer explanation

A right angle is defined as an angle that measures exactly 90 degrees. This is a fundamental concept in geometry, distinguishing it from other angles such as 45 degrees or 22 degrees.

Front

What is the measure of the missing angle?

Back

43

Answer explanation

To find the missing angle, subtract the sum of the known angles from 180 degrees. If the known angles add up to 137 degrees, then the missing angle is 180 - 137 = 43 degrees, making 43 the correct choice.

Front

Find the missing angle.

Back

47

Answer explanation

To find the missing angle, we can use the fact that the sum of angles in a triangle is 180 degrees. If the other two angles are known, subtract their sum from 180 to find the missing angle. Here, the missing angle is 47 degrees.

Front

Find the missing angle.

Back

28

Answer explanation

To find the missing angle, we can use the fact that the sum of angles in a triangle is 180 degrees. If the other two angles sum to 152 degrees, the missing angle is 180 - 152 = 28 degrees, making 28 the correct choice.

Front

Complementary angles are angles that add up to ___________.

Back

90 degrees

Answer explanation

Complementary angles are defined as two angles that sum up to 90 degrees. Therefore, the correct answer is 90 degrees, as it is the only option that fits this definition.

Front

What is the measure of the missing angle?

Back

72

Answer explanation

To find the missing angle, subtract the sum of the known angles from 180 degrees. If the known angles sum to 108 degrees, then the missing angle is 180 - 108 = 72 degrees. Thus, the correct answer is 72.

Front

Find the value of x.

Back

10

Answer explanation

To find the value of x, we can solve the equation provided. The correct answer is 10, as it satisfies the equation when substituted for x.

Front

Find the missing angle. Find x.

Back

20^o

Answer explanation

To find the missing angle x, we use the fact that the sum of angles in a triangle is 180°. If the other two angles are 70° and 90°, then x = 180° - 70° - 90° = 20°. Thus, the missing angle is 20°.