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    Given that the traingle ABD is equilateral and that C is the position of its centeroid find the y coordinate of C if D is the origin of a coordinate system.

    Also, the length of one side is 2d.
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    The centroid is a third of the perpendicular distance from the baseline to A. The baseline-A distance can be worked out from trig - if you take E to be the midpoint of BD, then the triangle ABE is right-angled with angles of 30 degrees and 60 degrees, from which you can use trig to work out AE in terms of d.
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    (Original post by TheDavibob)
    The centroid is a third of the perpendicular distance from the baseline to A. The baseline-A distance can be worked out from trig - if you take E to be the midpoint of BD, then the triangle ABE is right-angled with angles of 30 degrees and 60 degrees, from which you can use trig to work out AE in terms of d.
    Ahhhhh.... 1/3 the distance.... I see.

    I mistook it for half the length.

    Is it always 1/3 the distance for any triangle ?
 
 
 
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Updated: March 20, 2011
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