Angles

How do you measure an angle

Notes

What is an angle? How do you measure an angle?

Learn how to identify right, acute and obtuse angles.

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The different types of angles

Let's start with the right angle. Two perpendicular half lines form a right angle. This angle is important because it allows us to name the other angles. A right angle is an angle of 90 degrees.

An angle smaller than a right angle is called acute angle.

An angle larger than a right angle is called obtuse angle.

When two half lines are on the same line, they form a straight angle. A straight angle is 180 degrees and it's the double of a right angle.

When the two arms of the angle coincide, you can see an internal angle and an external angle:

  • a zero angle is 0 degrees;
  • full angle is 360 degrees.

What is an angle?

What is an angle?

The parts of an angle

The parts of an angle