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Lesson 1: Understanding angle measurement

# Measuring angles: FAQ

## 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, degrees, right angles measure exactly 90, degrees, and obtuse angles measure more than 90, degrees.
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.
Try it yourself with this exercise:

## 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.