00:01
Okay, so i have a circle, and i know part of a circle has a central angle of 135 degrees.
00:06
So the angle formed at the center of the circle is 135 degrees.
00:09
Find the area if the radius is 20 centimeters.
00:13
Okay, so what's the area of a circle in general? well, pi times my radius square.
00:20
Area of a sector, okay, so it's only a fraction of the circle, whatever that central angle is, divided by one whole revolution around the circle, is 306 degrees.
00:28
And if i'm in degrees, i can just write my angle in degrees as well.
00:34
So my area will be pi times my radius squared times 20 squared times 135, all divided by 360 degrees.
00:42
My degrees will end up canceling...