A circle has a diameter of 6 cm. A sector of the circle has a central angle of 80°. What is the area of this sector?
2007-10-09 12:06:32 · 4 answers · asked by Mike H 2 in Science & Mathematics ➔ Mathematics
find the area of the circle. The find out what percentage of 360 is 80 then mutiply that by the area of the circle.
2007-10-09 12:15:18 · answer #1 · answered by TheBrain 3 · 0⤊ 0⤋
The area is pi times the radius squared. The radius is 3, so the area is 9 time pi.
Next, you need to understand that as a circle has 360 degrees, a sector of 80 degrees represent 80/360 of the circle, or 2/9. Multiply this times the total area, and you'll have the area of the sector.
2007-10-09 19:16:03 · answer #2 · answered by TG 7 · 0⤊ 0⤋
The area of the whole circle would be pi x r squared (3.14 x 3x3) You only have 80/360 of a circle which is 2/9ths of a circle. So the area is 2/9 x 3.14x3x3 cm squared.
Hope this helps,
Fiona
http://www.confidentwoman.org.uk
2007-10-09 19:17:41 · answer #3 · answered by Fiona V 1 · 0⤊ 0⤋
Hello,
Set up a proportion:
x/80 = (PI*3^2)/360 so x = (80*pi*9)/360 then x = 2pi sq cm.
Hope this helps!!
2007-10-09 19:18:30 · answer #4 · answered by CipherMan 5 · 0⤊ 0⤋