Classifying and Measuring Angles Flashcards

What type of angle is represented by 90°?

What type of angle is represented by 180°?

What type of angle is represented by 38°?

What type of angle is represented by 125°?

Complementary angles have a sum of 90°.

If angle 1 measures 98° and angle 2 measures 72°, then the two angles are supplementary.

All pairs of vertical angles are equal.

Adjacent angles are always supplementary.

If angle 1 and angle 5 are vertical angles and angle 1 equals 55°, then angle 5 will equal ___.

If each of two complementary angles has the same measure, then each angle will equal ___.

In the diagram, if angle 7 equals 61°, what is the measure of angle 8?

If two angles are supplementary and one of the angles measures 38°, what is the measure of the larger angle?

Angle Classification

An angle measuring 90° is classified as a right angle.
An angle measuring 180° is classified as a straight angle.
An angle measuring less than 90° (e.g., 38°) is classified as an acute angle.
An angle measuring more than 90° but less than 180° (e.g., 125°) is classified as an obtuse angle.

Angle Relationships

Complementary angles are defined as two angles that add up to 90°.
If angle 1 measures 98° and angle 2 measures 72°, they are not supplementary because their sum is 170° (not equal to 180°).
All pairs of vertical angles are equal in measure, demonstrating the principle of angle equivalence.
Adjacent angles are not always supplementary; they can be any two angles that share a common vertex and side.

Angle Measurement Problems

If angle 1 and angle 5 are vertical angles and angle 1 measures 55°, angle 5 will also measure 55° due to their equal nature.
For two complementary angles with the same measure, each angle will be 45° since 45° + 45° = 90°.
Given that angle 7 is 61°, angle 8 can be determined as 119° since supplementary angles sum to 180° (180° - 61° = 119°).
If one angle in a supplementary pair measures 38°, the larger angle is 142° (180° - 38° = 142°).

Test your knowledge of angles with these flashcards. Each card presents an angle measurement along with its classification, ranging from right to obtuse and acute. Perfect for students learning basic geometry concepts.