document.write( "Question 241559: If a rectangle and a trapezoid have equal areas, then they must have the same
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document.write( "perimeters.
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document.write( "A) True
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document.write( "B) False \n" );
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Algebra.Com's Answer #176909 by Theo(13342)![]() ![]() You can put this solution on YOUR website! I would have to say no.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "This is because I found one instance where the areas are equal and the perimeters are not. That's all that's required to destroy the theory.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Consider that a parallelogram and a trapezoid both are composed of a square in the middle plus two triangles hanging at each end.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "I created two squares with 4 inches on each side.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "I then attached a triangle to the parallelogram on each end so that the resulting structure formed the parallelogram.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "each triangle was a 3/4/5 triangle.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "The one on the left had the 3 on top and the one on the right had the 3 on the bottom.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "The 5 of each triangle was the sides of the parallelogram.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the other sides of the parallelogram were formed from the 3 and the 5.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "A picture at the end will show you what I mean.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "The trapezoid was formed from the square with two triangles attached to it, 1 on each end.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "1 triangle was a 4/5/sqrt(41) triangle, and the other triangle was a 1/4/sqrt(17) triangle.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "The construction was such that the areas of the trapezoid and the parallelogram were equal.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "They are equal when b*h of the parallelogram = ((b1+b2)/2)*h of the trapezoid.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Since I made h of the parallelogram equal to h of the trapezoid, this meant that (b1+b2)/2 of the trapezoid equal to b of the parallelogram.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "I calculated the areas and they are equal.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "b of the parallelogram is equal to 7 (4 + 3)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "b1 + b2 of the trapezoid = 4 + 10 = 14\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "7*4 = 14/2*4 confirming the areas are equal.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "The perimeters, however, were not equal.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "7+7+5+5 of the parallelogram did not equal to 4+10+sqrt(41)+sqrt(17) of the trapezoid.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Theory doesn't hold.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Perimeters are not equal.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Picture of the resulting structures can be seen HERE !!!!!\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |