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# Equilateral Triangle watch

1. 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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2. 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.
3. (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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