A circle is dialated with a scale factor of 2/3. what is the area of the new circle if the area of the original circle is 45 square inches? Show your work. :)



Answer :

iGreen
Original Circle Area = 45

A = pi * r^2

Plug in what we know:

45 = 3.14 * r^2

Divide 3.14 to both sides:

14.3312102 = r^2

Find the square root of both sides:

r = 3.78565849

Find 2/3 of this:

2/3 * 3.78565849 = 2.52377233

So this is the radius of the newly dilated circle.

A = pi * r^2

A = 3.14 * 2.52377233^2

A = 3.14 * 6.36942677

A = 20

So the area of the newly dilated circle is 20 square inches.