The area of a sector of a circle of radius 12cm is 188.5cm^2. Find the central angle contained in the sector in: a) radians b) degrees.
I cannot get their answers which are 2.618 rads and 150 degrees. I used the area of a sector formula A = 1/2r^2theta, substituted the values I have in and rearranged but I get 116.5 and can't work out where I'm going wrong.
Please explain :)
I cannot get their answers which are 2.618 rads and 150 degrees. I used the area of a sector formula A = 1/2r^2theta, substituted the values I have in and rearranged but I get 116.5 and can't work out where I'm going wrong.
Please explain :)
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1/2 r² θ = A
1/2 * 144 θ = 188.5
72θ = 188.5
θ = 188.5/72
θ = 2.618 radians
θ = 188.5/72 * 180/π
θ = 150 degrees
Mαthmφm
1/2 * 144 θ = 188.5
72θ = 188.5
θ = 188.5/72
θ = 2.618 radians
θ = 188.5/72 * 180/π
θ = 150 degrees
Mαthmφm
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A = 1/2r^2theta
188.5 = (1/2)(144)theta
377 = 144theta
2.618 = theta
to convert to degrees multipy 360 degrees & divide by 2*pi
188.5 = (1/2)(144)theta
377 = 144theta
2.618 = theta
to convert to degrees multipy 360 degrees & divide by 2*pi