A 45 degree sector in a circle has an area of 43.2 centimeters squared.

What is the area of the circle?

Answer: The area of the circle is 345.6 cm^2.

If you have a 45 degree sector, that is 1/8 of the total area of the circle.

45/360 = 1/8

So simply, multiply the known area by 8 and you will have the total area.

43.2 x 8 = 345.6 cm^2 is the area of the entire circle.