Let rectangle ABCD have lengths AB=20 and BC=12. Extend ray BC to Z such that CZ=18. Let E be the point in the interior of ABCD such that the perpendicular distance from E to A B} is 6 and the perpendicular distance from EtoAD is 6 . Let line EZ intersect AB at X and CD at Y. Find the area of quadrilateral AXYD.
A number or a short expression. Fractions can be typed as 3/2, and spacing doesn't matter.
Solution
Draw the line parallel to A D}throughE,intersectingAB at F and C D}atG.ItisclearthatX F EandY G E are congruent, so the area of A X Y DisequaltothatofA F G D.ButA F G D is simply a 12 by 6 rectangle, so the answer must be 72 . (Note: It is also possible to directly compute the values of A XandD Y$, then use the formula for the area of a trapezoid.)
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