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Math Help - trapezoid

  1. #1
    Member helloying's Avatar
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    trapezoid

    thanks
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  2. #2
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    Quote Originally Posted by helloying View Post
    thanks
    Cut off thetwo right triangles of the trapezium (see attachment)

    Then you know

    (A) \dfrac hx=\tan(72^\circ) ........ and ........ (B) \dfrac hy = \tan(68^\circ)

    According to my sketch you can see that

    x+y=8~\implies~y=8-x

    Solve the equations (A) and (B) for h and substitute (8-x) instead of y:

    x\tan(72^\circ) = (8-x) \tan(68^\circ)

    Solve for x. I've got x \approx 3.5659 and consequently y \approx 4.4341 and h \approx 10.9747

    I'll leave the rest for you.
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