Angle Measure: Degrees
A full turn is 360°; angles measure rotation.
Key idea
A full turn is 360°; angles measure rotation.
In depth
A degree is 1/360 of a full turn. The number 360 was chosen long ago because it has many divisors, so common fractions of a circle are whole numbers of degrees. Right angle = 90°, straight = 180°, full turn = 360°.
Worked example
A quarter turn is 90°; three quarters is 270°.
Real-world uses
- Describing compass directions, turning angles in sport and rotation of machines
Common mistake
Mixing degrees and radians on a calculator. Check the mode.
How to learn this
- Read the key idea and say it in your own words.
- Work through the worked example, then try a similar problem.
- Use the interactive lesson’s visual and mini-quiz to check the pattern.
Frequently asked questions
What is Angle Measure: Degrees?
A full turn is 360°; angles measure rotation. It is a topic at the beginner level in Trigonometry.
Where is Angle Measure: Degrees used in real life?
Real-world examples: Describing compass directions, turning angles in sport and rotation of machines.
What should I learn before Angle Measure: Degrees?
It is the first topic in Trigonometry, so no earlier topic in this area is needed.
What is a common mistake with Angle Measure: Degrees?
Mixing degrees and radians on a calculator. Check the mode.
How can I practise Angle Measure: Degrees?
Open the interactive lesson, play with the visual, then answer the three-question mini-quiz. Getting two right marks the topic complete.
What comes after Angle Measure: Degrees?
Move on to Radians next.
Related beginner topics in Trigonometry
- Right Triangle Terminology – Hypotenuse, opposite and adjacent sides relative to an angle.
- SOH-CAH-TOA – Memory aid for the three basic ratios.