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diagram

How do I find the coordinates ?/? (green star) given n, A (angle) and x'/y' (red circle)? NOTE: The n on the left side is vertical, while the n on the right side is at A angle from this vertical line.

I'm sure if I knew the correct term to ask for I'd be able to locate the answer within the site, but alas, I was stretching to use the term "isosceles triangle" correctly =) Many thanks for any help you can provide!

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    @Gerry Myerson: Yes, the "left" `n` is indeed vertical! I'm trying to solve this problem: http://stackoverflow.com/questions/10508022/points-on-a-unrotated-rectangle in order to solve this problem: http://stackoverflow.com/questions/10392658/calculate-the-bounding-boxs-x-y-height-and-width-of-a-rotated-element-via-jav2012-05-10

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Let the unknown point have co-ordinates $(r,s)$. Then $\sin A=(x'-r)/n$ and $\cos A=(y'-s)/n$, where $(x',y')$ is the known point. So $r=x'-n\sin A$ and $s=y'-n\cos A$.

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    @Ross, my formulas are not in any particular units. If $A$ is given as 30 degrees, then the formula calls for the sine of 30 degrees. If $A$ is given as pi-over-6 radians, then the formula calls for the sine of pi-over-6 radians. An angle is what it is, no matter how you measure it, and its sine is opposite over hypotenuse, no matter how you measure it.2012-05-11