# Complementary and supplementary angles worksheet (with answer key + pdf)

Introduction:

Supplementary and complementary angles are defined by the sum of two angles. If the total of two angles is 180 degrees, they are considered to be supplementary angles since they produce a linear angle when combined.

If the total of two angles is 90 degrees, they are considered to be complementary angles since they produce a right angle when combined.

When two line segments or lines cross at a common point (called a vertex), an angle is generated at the point of intersection.

When a ray is rotated about its terminus, the angle created between its starting and final positions is the measure of its rotation in an anti-clockwise orientation.

## What are the complementary angles?

When the total of two angles is 90°, the angles are said to be complementary. In other words, if two angles add up to make a right angle, they are called complementary angles.

The two angles are said to complement each other in this context.

## What are supplementary angles?

When the sum of two angles is 180°, then the angles are known as supplementary angles. In other words, if two angles add up, to form a straight angle, then those angles are referred to as supplementary angles.

This worksheet will help you to understand whether the two angles are complementary or supplementary. It will challenge the student’s ability to identify them.

## Instructions on using the “Complementary and supplementary angles worksheet pdf with answers”:

Using this math worksheet you learn about Complementary and supplementary angles.

A reflection section is included at the end of this worksheet to assist the student think about their thinking (metacognition) and analyse how they performed in the session.

Finally, it challenges the student to devise their problems and compare them with the ones he/she learned from the worksheet.

## Conclusion:

This worksheet will help you gain the essential skills for identifying and calculating angles.