document.write( "Question 25756: In a diagram of a large quadrilateral, AD is parallel to BC, BD is perpendicular to DC, and AE is perpendicular to BD.
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document.write( "AB is 41 cm, AD is 50 cm and BF is 9 cm.
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document.write( "What is the area of the small quadrilateral, DCEF? \n" );
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Algebra.Com's Answer #13906 by keigan(2)![]() ![]() ![]() You can put this solution on YOUR website! The area of DCEF is 960 cm^. \n" ); document.write( "Using Pythagoras, AF = 40cm and FD = 30cm. \n" ); document.write( "Triangles ADF and BFE are similar, so FE = 12 cm. \n" ); document.write( "BD = BF + FD = 39cm. \n" ); document.write( "Triangles BDC and BFE are similar, so DC = 52cm. \n" ); document.write( "DCEF is a trapezium with height DF. \n" ); document.write( "Area of DCEF is ( (FE + DC) x FD) )/2 = 960 cm^. \n" ); document.write( " |