Geometry
posted by Courtney on .
The measure of the central angle of a sector of a circle is 90degrees. The arc length of the sector is 3(pie) cm. What is the radius of the circle?

The circumference of the circle = 2 r pi
The measure of the sector 90 ° = ( 1 / 4 ) 2 r pi = r pi / 2
r pi / 2 = 3 pi Divide both sides by pi
r / 2 = 3 Multiply both sides by 2
r = 2 * 3
r = 6 cm 
Thanks so much!

A circke has an arc length of 10 feet. The central angle formed os 60°. What is the area of the sector?