What is the area of a circle with radius 5?
Answer and explanation
Correct answer: D. 25 pi, from pi times 5 squared
- Step 1: The area formula is A = pi r^2. Step 2. With r = 5 this is 25 pi. Answer: 25 pi. Why not the others: 10 pi is the circumference, and the others do not use the square of the radius.
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