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Introduction Introduction # Complementary and Supplementary Angles

INTRO
Complementary and supplementary angles are special pairs of angles 👯‍♀️.
Complementary angles are two angles that combine to form a corner.
Supplementary angles are two angles that combine to form a straight line.
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Lesson
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Practice

CALCULATOR

## Complementary & Supplementary Angles Calculator

Are the two angles complementary or supplementary?
KEY STEPS

## How to Find Complementary & Supplementary Angles

Show steps for angles that are:

### Step 1. Determine the total angle measure.

If the two angles are complementary or form a corner (right angle), then the total angle measure is .

### Step 2. Find the value of the unknown angle.

If we know the measure of one of the two angles, we can use it to find the value of the missing angle.
LESSON
Complementary and Supplementary Angles

## Complementary and Supplementary Angles

Complementary and supplementary angles problems come in a few different forms. Sometimes, you'll be given a diagram with one given angle and one unknown angle:

In this case, the little box 🔲 in the corner tells us the two angles are complementary and add up to .
And if you see two angles on a straight line like this:
You'll know that the two angles are supplementary and add up to .
PRACTICE
Complementary and Supplementary Angles

## Practice: Complementary & Supplementary Angles

Question 1 of 10: Find the unknown angle:

### Step 1. Determine the total angle measure.

What is the total angle measure?

CONCLUSION
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