Question

Alyssa figured the area of a circle to be 75 mm². If its radius is doubled, the new area would be _____ mm².

100
150
300
350

@ajwrstlr397

Answer 1

Original radius = r
Original area = pi*r^2 = 75
New radius = 2r
New area = pi*(2r)^2 = pi*4*r^2

The new area is 4 times as big as the old area, so the new area is 4*75 = 300, which is answer (c).

Answer 2

thank you so much

Answer 3

You welcome :)