document.write( "Question 1079613: graph a quadrilateral with points of A(6,5), B(-3,-1), C(-1,-4), D(8,2)
\n" ); document.write( "what type of quadrilateral is ABCD? Use slope to justify my answer
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Algebra.Com's Answer #693843 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Graph:\r
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\n" ); document.write( "\n" ); document.write( "Let's find the slopes of the four sides (AB, BC, CD, DA)\r
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\n" ); document.write( "\n" ); document.write( "Slope of AB\r
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\n" ); document.write( "\n" ); document.write( "\"m+=+%28y%5B2%5D+-+y%5B1%5D%29%2F%28x%5B2%5D+-+x%5B1%5D%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"m+=+%28-1+-+5%29%2F%28-3+-+6%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"m+=+%28-6%29%2F%28-9%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"m+=+2%2F3\"\r
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\n" ); document.write( "\n" ); document.write( "Slope of BC\r
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\n" ); document.write( "\n" ); document.write( "\"m+=+%28y%5B2%5D+-+y%5B1%5D%29%2F%28x%5B2%5D+-+x%5B1%5D%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"m+=+%28-4+-+%28-1%29%29%2F%28-1+-+%28-3%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"m+=+-3%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "Slope of CD\r
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\n" ); document.write( "\n" ); document.write( "\"m+=+%28y%5B2%5D+-+y%5B1%5D%29%2F%28x%5B2%5D+-+x%5B1%5D%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"m+=+%282+-+%28-4%29%29%2F%288+-+%28-1%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"m+=+%286%29%2F%289%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"m+=+2%2F3\"\r
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\n" ); document.write( "\n" ); document.write( "Slope of DA\r
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\n" ); document.write( "\n" ); document.write( "\"m+=+%28y%5B2%5D+-+y%5B1%5D%29%2F%28x%5B2%5D+-+x%5B1%5D%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"m+=+%285+-+2%29%2F%286+-+8%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"m+=+%283%29%2F%28-2%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"m+=+-3%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "In summary so far, we have\r
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\n" ); document.write( "\n" ); document.write( "Slope of AB = 2/3\r
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\n" ); document.write( "\n" ); document.write( "Slope of BC = -3/2\r
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\n" ); document.write( "\n" ); document.write( "Slope of CD = 2/3\r
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\n" ); document.write( "\n" ); document.write( "Slope of DA = -3/2\r
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\n" ); document.write( "\n" ); document.write( "Notice how the opposite sides have equal slopes (AB and CD have same slope; BC and DA have same slope). This means we have parallel opposite sides.\r
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\n" ); document.write( "\n" ); document.write( "Parallel lines have equal slopes.\r
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\n" ); document.write( "\n" ); document.write( "So this figure is a parallelogram. \r
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\n" ); document.write( "\n" ); document.write( "More specifically this figure is a rectangle because the sides are perpendicular. How do we know this? Because the product of the non-equal adjacent slopes is -1\r
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\n" ); document.write( "\n" ); document.write( "For instance, (slope of AB)*(slope of BC) = (2/3)*(-3/2) = -1. This particular example shows how AB is perpendicular to BC. \r
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\n" ); document.write( "\n" ); document.write( "Since the adjacent sides are perpendicular, four right angles form to have this figure be a rectangle.\r
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\n" ); document.write( "\n" ); document.write( "Final Answer: The figure is a rectangle
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