document.write( "Question 77881: 1. Find the length of a shorter leg of a right triangle if the longer leg is 10 miles more than the shorter leg and the hypotemuse is 10 miles less than twice the shorter leg.\r
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Algebra.Com's Answer #55990 by ankor@dixie-net.com(22740)\"\" \"About 
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1. Find the length of a shorter leg of a right triangle 1. Find the length of a shorter leg of a right triangle if the longer leg is 10 miles more than the shorter leg and the hypotenuse is 10 miles less than twice the shorter leg.
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\n" ); document.write( "Using pythag: a^2 + b^2 = c^2
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\n" ); document.write( "Let x = a: the shorter leg
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\n" ); document.write( "\"longer leg is 10 miles more than the shorter leg\"
\n" ); document.write( "b = (x+10)
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\n" ); document.write( "\"the hypotenuse is 10 miles less than twice the shorter leg.\"
\n" ); document.write( "c = (2x - 10)
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\n" ); document.write( "a^2 + b^2 = c^2 is:
\n" ); document.write( "x^2 + (x+10)^2 = (2x-10)^2
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\n" ); document.write( "x^2 + (x^2 + 20x + 100) = 4x^2 - 40x + 100
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\n" ); document.write( "2x^2 + 20x + 100 = 4x^2 - 40x + 100
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\n" ); document.write( "0 = 4x^2 - 2x^2 - 40x - 20x + 100 - 100
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\n" ); document.write( "2x^2 - 60x = 0; a simple equation
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\n" ); document.write( "Factors to:
\n" ); document.write( "2x(x - 30) = 0
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\n" ); document.write( "2x = 0
\n" ); document.write( "and
\n" ); document.write( "x = 30 the length of the shorter side
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\n" ); document.write( "Check; a^2 + b^2 = c^2:
\n" ); document.write( "30^2 + 40^2 = (60-10)^2
\n" ); document.write( "900 + 1600 = 50^2 = 2500
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\n" ); document.write( "2. \"The sum of two numbers is twenty five\"
\n" ); document.write( "x + y = 25
\n" ); document.write( "y = (25 - x)
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\n" ); document.write( "\"the sum of their squares is three hundred and five\"
\n" ); document.write( "x^2 + y^2 = 305
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\n" ); document.write( "Find the number.
\n" ); document.write( "Substitute (25-x) for y in the 2nd equation:
\n" ); document.write( "x^2 + (25-x)^2 = 305
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\n" ); document.write( "x^2 + 625 - 50x + x^2 = 305
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\n" ); document.write( "2x^2 - 50x + 625 - 305 = 0
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\n" ); document.write( "2x^2 - 50x + 320 = 0
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\n" ); document.write( "There is no solution: Look at the discriminant of this equation:
\n" ); document.write( " -b^2 - 4 * a * c
\n" ); document.write( "-50^2 - 4 * 2 * 320
\n" ); document.write( "2500 - 2560 = -60; <0 means x has no real solutions
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\n" ); document.write( "If we graph the two equations:
\n" ); document.write( "y = 25-x
\n" ); document.write( "y = Sqrt(305 - x^2)
\n" ); document.write( "\"+graph%28+300%2C+200%2C+-2%2C+20%2C+-2%2C+20%2C+25-x%2C+sqrt%28305-x%5E2%29%29+\"
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\n" ); document.write( "No point of intersection
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