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### Course: 4th grade > Unit 12

Lesson 1: Understanding angle measurement# Measuring angles: FAQ

Frequently asked questions about measuring angles.

## What is an angle?

An angle is a way of measuring how much two lines, or "rays," are pointing away from each other. When two lines intersect (or cross), they create an angle. We can measure the size of that angle in degrees.

Try it yourself with these exercises:

## What's the difference between acute, right, and obtuse angles?

Acute angles measure less than ${90}^{\circ}$ , right angles measure exactly ${90}^{\circ}$ , and obtuse angles measure more than ${90}^{\circ}$ .

Try it yourself with these exercises:

## What are benchmark angles?

Benchmark angles are common angles that we use to help us estimate the measure of other angles. For example, a right angle is a benchmark angle.

Try it yourself with this exercise:

## What does it mean to decompose an angle?

When we decompose an angle, we break it down into smaller angles that add up to the original angle.

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## Where do we use angles in the real world?

There are countless ways that angles are used in the real world!

Here are just a few examples:

- In construction, angles are essential for determining the correct shapes and dimensions of structures. For example, carpenters need to measure and cut angles to build frames for doors, windows, and roofs.
- In sports, athletes often use angles to their advantage. A basketball player, for example, will aim the ball at a certain angle to maximize their chances of making a shot. A baseball pitcher might throw a curveball by altering the angle of their wrist.
- When drawing or coloring, we might use angles to make sure the lines and shapes we're creating look the way we want them to.

## Want to join the conversation?

- Use a protractor to measure angles it will help you!(23 votes)
- and what is a protactor??(0 votes)

- Okay, I don't know who needs this but here. When you get to lesson 2 remember to put the dots in front of the number but on the line. You'll understand soon enough. Then for a recap 90 degrees is a right angle. anything less then 90 is acute, anything more is obtuse. 180 is half a circle and a full circle is 360. There are only three lessons in this unit i think. Good luck(14 votes)
- do you mean a full circle is 360 degrees(11 votes)

- This is so easy khan academy(6 votes)
- this is fun(4 votes)
- is a right angle always on the right?(4 votes)
- What If there are other objects that aren't any type of angle but the do have a angle.(2 votes)
- who is here that’s actually older and doing grade 8 math but here to help kids with math lol(1 vote)
- What is a 90 degree angle?(1 vote)
- it is a type of angle that looks like an L. dont let that fool you though. make sure to use a protrator so you know for sure if it is 90 degrees.(1 vote)

- I feel like doing it in real life and having a protracter would be easier.(1 vote)