Math/Trig
posted by Tabitha on .
Find the area of a sector of a circle with a radius of 3 m and a central angle of 125degrees.

Area K = 1/2 r^2 * angle in rads
Convert deg to rads
125 deg * pi/180 = 25pi/36 rads
K = 1/2 * 3^2 * 25pi/36
K = ? m^2
you do the math
Area K is expressed in m^2 (in this case) 
area of whole circle = 9π
area of sector = (125/360)(9π) = appr. 9.8 m^2 
Area of circle:
A=r^2*pi
Area of your sector=r^2*pi*(125/360)=3^2*pi*125/360=9*pi*125/360
=9*3.1415926535*125/360
=3534,2917351875/360
=9,8174770421875 m^2