Measurement · Challenge 16 of 25 · about 4 min
Identify a Reflex Angle
Classify an angle using quarter-turn landmarks rather than measuring degrees.
Your challenge
Take your time. Your answer is checked only when you choose Check Answer.
Curriculum details
- Curriculum code
- VC2M4M04
- Strand
- Measurement
- Focus
- Compare an angle with right, straight and full-turn benchmarks.
Interactive visual
An interactive Use quarter-turn landmarks model is ready. Choose Show Visual Trick to reveal and hear one mathematical change at a time.
Visual Trick
Use quarter-turn landmarks
One right angle is a quarter turn, a straight angle is a half turn, and a revolution is a full turn.
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Step 1
Rotate one right angle to show a quarter turn.
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Step 2
Rotate through two right angles to show a straight angle.
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Step 3
Continue past three right angles without completing four.
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Step 4
Classify the angle between a straight angle and a revolution as reflex.
Your answer
Worked explanation
Why the answer makes sense
- A straight angle is a half turn.
- A complete revolution is a full turn.
- An angle between those landmarks is a reflex angle.
This counts as one completed curriculum item. You can replay the model or review it again anytime.