Question

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Calculate the area of a circle with a radius of 2 cm and a circle with a radius of 4 cm. Leave your answers in terms of pi.

When the radius doubles, does the area of the circle double?
A) 4π cm2; 8π cm2; NO
B) 4π cm2; 16π cm2; NO
C) 4π cm2; 16π cm2; YES
D) 4π cm2; 8π cm2; YES

Answer 1

C?

Answer 2

@Vocaloid

Answer 3

A = pi * r^2
they want the answer in terms of pi so leave pi alone and simplify everything else

first use r = 2 and then use r = 4, then compare the two areas

Answer 4

okay, thnx so much