document.write( "Question 340347: if the length of the diagonal of a rectangle is 50 in. and its area isa 1200 in.squared, what are its dimensions? \n" ); document.write( "
Algebra.Com's Answer #243893 by solver91311(24713)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "As soon as I see a hypotenuse that measures some multiple of 5, I always suspect that I am dealing with a 3-4-5 right triangle. Sure enough, 30 times 40 is 1200. And there's the answer without doing any work. But I suspect you need to see the method, so here goes:\r
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\n" ); document.write( "\n" ); document.write( "Let represent one leg of the triangle (which is to say one dimension of the rectangle) and let represent the other leg.\r
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\n" ); document.write( "\n" ); document.write( "Since we know the area to be 1200 square inches, we can write:\r
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\n" ); document.write( "\n" ); document.write( "From which we can derive:\r
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\n" ); document.write( "\n" ); document.write( "From the Pythagorean Theorem we know:\r
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\n" ); document.write( "\n" ); document.write( "Substituting:\r
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\n" ); document.write( "\n" ); document.write( "Which is to say:\r
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\n" ); document.write( "\n" ); document.write( "Multiply both sides by \r
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\n" ); document.write( "\n" ); document.write( "Ewww -- that's ugly! Not to worry though.\r
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\n" ); document.write( "\n" ); document.write( "Let , substitute, and gather everything on the left:\r
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\n" ); document.write( "\n" ); document.write( "Hmmm, 16 times 9 is 144 and 16 plus 9 is 25...\r
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\n" ); document.write( "\n" ); document.write( "So:\r
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\n" ); document.write( "\n" ); document.write( "and\r
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\n" ); document.write( "\n" ); document.write( "Toss the negative roots (we are looking for positive measures of length) and if , then or if , then \r
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\n" ); document.write( "\n" ); document.write( "And there you have it.\r
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\n" ); document.write( "\n" ); document.write( "John
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\n" ); document.write( "My calculator said it, I believe it, that settles it
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