Please help me geometry proof for trapezoid
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A trapezoid is a quadrilateral that has two parallel sides with a height.
From the diagram, AK = 1/2(AD-BC)
The combination of the bases of the equilateral triangle and the parallelogram is = the base of the trapezoid.
Therefore, BC = AD - 2AK
Make AK the subject of formula,
AK= 1/2 (AD -BC)
KD = 1/2(AD - BC). This is wrong because of the following,
BC is parallel to KD.
Therefore length of KD = BC - AK and not KD = 1/2(AD - BC).
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