Geometry and TrigonometryEasyDiameter of a circle from its equation
Geometry and Trigonometry practice question
In the xy-plane, the circle x² + y² = 16 has a radius of 4. What is the length of its diameter?
Answer: 8
The diameter is twice the radius: 2 × 4 = 8.
Common wrong answers
- If you answered 2
- 2 halves the radius.
- If you answered 4
- 4 is the radius.
- If you answered 16
- 16 is r².
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