# Lesson 13 Find Angle Measurements

• Let’s compose and decompose angles to find their measurements.

## Warm-up Notice and Wonder: Corner Pieces

What do you notice? What do you wonder?

## Problem 1

Your teacher will give you materials that can help you find angle measurements.
Use the materials and what you know about a right angle to find the size of angles , , , and . Be prepared to explain or show your reasoning.

## Problem 2

Next, use the measurements of angles , , , and to find the measurements of the following angles.

## Activity 2 Angles in a Kite

Your teacher will give you a square sheet of paper. Follow the steps to fold the paper into a kite. Fold as precisely as possible.

Can you find the measurement of each labeled angle on the kite? If so, show your reasoning. If not, explain why not.

## Problem 1

1. The circle is divided into 12 equal parts. What is the measure of angle ?

Explain or show how you know.

2. Can you put together angles to make a circle? How many of them will it take?

## Problem 2

1. A circle has been cut into eighths. How many degrees is the angle labeled ? Explain or show your reasoning.

2. Another circle has been cut into fifths. How many degrees is the angle labeled ? Explain or show your reasoning.

## Problem 3

1. What is the measure of each angle ? Explain or show how you know.

2. How many angles can you fit together at one vertex without gaps or overlaps?