Question

Circle J was dilated to form circle J'. The diameter of circle J is 2 units and the diameter of circle J' is 18 units. What is the relationship between the areas of circle J and circle J'?

Answer 1

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Answer:

circle J' has 81 times the area of circle J

Explanation:

The ratio of areas is the square of the dilation factor. That factor is 18/2 = 9, so the dilated circle has an area that is 9² = 81 times that of the original.