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    The area of a segment is 20cm^2 and the angle subtended by the chord forming the segment is 1.3 radians. What is the radius of the circle?
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    a = 0.5r^2 (theta)

    r= 5.54 cm
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    The first question was just putting numbers into the formula for area of a segment.

    Another little area of segments question.

    A chord divides a circle into 2 areas, in the ratio 3:1.

    What is the angle between the chord and a diameter drawn from one of its endpoints?
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    (Original post by callum Honisett)
    a = 0.5r^2 (theta)

    r= 5.54 cm
    http://www.mathsisfun.com/geometry/i...cle-slices.gif

    The area of the segment is 20cm2 - not the area of the sector.
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    (Original post by stevencarrwork)
    The first question was just putting numbers into the formula for area of a segment.

    Another little area of segments question.

    A chord divides a circle into 2 areas, in the ratio 3:1.

    What is the angle between the chord and a diameter drawn from one of its endpoints?
    Is it pi/2 rad.
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    (Original post by Narik)
    http://www.mathsisfun.com/geometry/i...cle-slices.gif

    The area of the segment is 20cm2 - not the area of the sector.
    Oh sorry must have msiread it :rolleyes:

    I'll get to it in a minute.
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    (Original post by Narik)
    http://www.mathsisfun.com/geometry/i...cle-slices.gif

    The area of the segment is 20cm2 - not the area of the sector.
    (0.5r^2 theta) - (0.5r^2sintheta) = 20

    (you know theta, can't remember what you said it was)
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    CALLUM
    Is it pi/2 rad.

    ME

    I see where you are coming from, but that would be the angle joining the other end of the chord to the diameter drawn from the first end.

    That line is a distraction. (Or at least I think there is an easier way)
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    (Original post by Narik)
    http://www.mathsisfun.com/geometry/i...cle-slices.gif

    The area of the segment is 20cm2 - not the area of the sector.
    In that case you will need the 0.5*a*b*SinC rule as well.
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    Just use this formula:

     Area\ of\ segment = \frac{1}{2}r^2(\theta - \sin \theta)

    And rearrange to find r.
 
 
 
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