The equation that sets the ratio of θ to the area of sector BAC equal to the ratio of 360 to the area of the circle shown above.
To see why this is so.....let the radius = 1
So the area of the circle = pi(1)^2 = pi
Now....imagine that θ = 60°
So
60 / area of sector = 360 / pi
60 /area of sector = 360 /pi we can write
area of sector / 60 = pi /360 multiply both sides by 60
area of sector = (60 /360) pi = pi /6
Since 60° is 1/6 of 360°.....the area should be (1/6) pi = pi /6
