document.write( "Question 612626: one leg of a right triangle measures three inches less than the other leg. find the length of both legs if the hypotenuse is 4 inches long \n" ); document.write( "
Algebra.Com's Answer #385632 by nerdybill(7384)\"\" \"About 
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one leg of a right triangle measures three inches less than the other leg. find the length of both legs if the hypotenuse is 4 inches long
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\n" ); document.write( "Let x = longer leg
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\n" ); document.write( "x-3 = shorter leg
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\n" ); document.write( "applying Pythagorean theorem:
\n" ); document.write( "x^2 + (x-3)^2 = 4^2
\n" ); document.write( "x^2 + (x-3)(x-3) = 16
\n" ); document.write( "x^2 + x^2-6x+9 = 16
\n" ); document.write( "2x^2-6x+9 = 16
\n" ); document.write( "2x^2-6x-7 = 0
\n" ); document.write( "applying the \"quadratic formula\" yields:
\n" ); document.write( "x = {3.9, -0.9}
\n" ); document.write( "throw out the negative solution (extraneous) leaving
\n" ); document.write( "x = 3.9 inches (longer leg)
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\n" ); document.write( "shorter leg:
\n" ); document.write( "x-3 = 3.9-3 = .9 inches
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\n" ); document.write( "answer: 3.9 inches and .9 inches
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\n" ); document.write( "details of quadratic formula follows:
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"2x%5E2%2B-6x%2B-7+=+0\") has the following solutons:
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\n" ); document.write( " \"x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
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\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
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\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%28-6%29%5E2-4%2A2%2A-7=92\".
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\n" ); document.write( " Discriminant d=92 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--6%2B-sqrt%28+92+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%28-6%29%2Bsqrt%28+92+%29%29%2F2%5C2+=+3.89791576165636\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28-6%29-sqrt%28+92+%29%29%2F2%5C2+=+-0.89791576165636\"
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\n" ); document.write( " Quadratic expression \"2x%5E2%2B-6x%2B-7\" can be factored:
\n" ); document.write( " \"2x%5E2%2B-6x%2B-7+=+2%28x-3.89791576165636%29%2A%28x--0.89791576165636%29\"
\n" ); document.write( " Again, the answer is: 3.89791576165636, -0.89791576165636.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+2%2Ax%5E2%2B-6%2Ax%2B-7+%29\"
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