Question

Circle D was dialated to form circle D'. The diameter of circle D is 5 units and the diameter of circle D' is 15 units. What is the relationship between the areas of circle D and circle D'?

A The area of circle D' would be 3 times the area.

B The area of circle D' would be 9 times the area.

C The area of circle D' would be 1/3 of the original area.

D The area of circle D' would be 1/9 of the original area.
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Answer 1

Let A1 be original area

A2 dilated Area

A1=pi*d^2/4

=3.143*5^2/4

A1=19.63 unit square

A2= 3.143*15/4

A2=176.74 unit square

A2 is 9 times greater than A1

Hence the answer is B

Explanation: