document.write( "Question 181935: the length of one leg of a right triangle is 7 meters less than the length of the other leg. the length of the hypotenuse is 13 meters. find the lengths of the legs. \n" ); document.write( "
Algebra.Com's Answer #136555 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "We basically have this triangle set up:\r
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\n" ); document.write( "\n" ); document.write( "Since the legs are \"x\" and \"x-7\" this means that \"a=x\" and \"b=x-7\"\r
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\n" ); document.write( "\n" ); document.write( "Also, since the hypotenuse is \"13\", this means that \"c=13\".\r
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\n" ); document.write( "\n" ); document.write( "\"a%5E2%2Bb%5E2=c%5E2\" Start with the Pythagorean theorem.\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B%28x-7%29%5E2=13%5E2\" Plug in \"a=x\", \"b=x-7\", \"c=13\" \r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B%28x-7%29%5E2=169\" Square \"13\" to get \"169\".\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2Bx%5E2-14x%2B49=169\" FOIL\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2Bx%5E2-14x%2B49-169=0\" Subtract 169 from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"2x%5E2-14x-120=0\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "Notice we have a quadratic equation in the form of \"ax%5E2%2Bbx%2Bc\" where \"a=2\", \"b=-14\", and \"c=-120\"\r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for x\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4ac+%29%29%2F%282a%29\" Start with the quadratic formula\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-%28-14%29+%2B-+sqrt%28+%28-14%29%5E2-4%282%29%28-120%29+%29%29%2F%282%282%29%29\" Plug in \"a=2\", \"b=-14\", and \"c=-120\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2814+%2B-+sqrt%28+%28-14%29%5E2-4%282%29%28-120%29+%29%29%2F%282%282%29%29\" Negate \"-14\" to get \"14\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2814+%2B-+sqrt%28+196-4%282%29%28-120%29+%29%29%2F%282%282%29%29\" Square \"-14\" to get \"196\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2814+%2B-+sqrt%28+196--960+%29%29%2F%282%282%29%29\" Multiply \"4%282%29%28-120%29\" to get \"-960\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2814+%2B-+sqrt%28+196%2B960+%29%29%2F%282%282%29%29\" Rewrite \"sqrt%28196--960%29\" as \"sqrt%28196%2B960%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2814+%2B-+sqrt%28+1156+%29%29%2F%282%282%29%29\" Add \"196\" to \"960\" to get \"1156\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2814+%2B-+sqrt%28+1156+%29%29%2F%284%29\" Multiply \"2\" and \"2\" to get \"4\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2814+%2B-+34%29%2F%284%29\" Take the square root of \"1156\" to get \"34\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2814+%2B+34%29%2F%284%29\" or \"x+=+%2814+-+34%29%2F%284%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2848%29%2F%284%29\" or \"x+=++%28-20%29%2F%284%29\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+12\" or \"x+=+-5\" Simplify. \r
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\n" ); document.write( "\n" ); document.write( "So the possible answers are \"x+=+12\" or \"x+=+-5\" \r
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\n" ); document.write( "\n" ); document.write( "However, a negative length is NOT possible. So \"x+=+-5\" is NOT a solution\r
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\n" ); document.write( "\n" ); document.write( "So the only answer is \"x+=+12\" \r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
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\n" ); document.write( "\n" ); document.write( "So the solution is \"x+=+12\"\r
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\n" ); document.write( "\n" ); document.write( "This means that the other leg is \"12-7=5\"\r
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\n" ); document.write( "\n" ); document.write( "So the two legs are: 12 and 5 units
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