document.write( "Question 389474: A right triangle has area 19 and the sum of its two legs is 20. Compute the length of the hypotenuse. \n" ); document.write( "
Algebra.Com's Answer #276004 by MathLover1(20849)\"\" \"About 
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A right triangle has area 19 and the sum of its two legs is 20. Compute the length of the hypotenuse.\r
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\n" ); document.write( "\n" ); document.write( "given:\r
\n" ); document.write( "\n" ); document.write( "area \"A=19+\"\r
\n" ); document.write( "\n" ); document.write( "and the sum of its two legs \"a%2Bb\" is \"20\"\r
\n" ); document.write( "\n" ); document.write( "find: the length of the hypotenuse \"c\"\r
\n" ); document.write( "\n" ); document.write( "The sides \"a\", \"b\", and \"c\" of a right triangle satisfy the Pythagorean theorem, so\r
\n" ); document.write( "\n" ); document.write( "\"c%5E2+=+a%5E2+%2B+b%5E2\"\r
\n" ); document.write( "\n" ); document.write( "the area is \"A=%281%2F2%29ab+\"\r
\n" ); document.write( "\n" ); document.write( "now, find \"a\" and \"b\"\r
\n" ); document.write( "\n" ); document.write( "\"A=%281%2F2%29ab+\".....................1\r
\n" ); document.write( "\n" ); document.write( "\"a%2Bb=+20\"...........................2.........solve for \"a\"...\"a=+20-b\". and substitute in 1\r
\n" ); document.write( "\n" ); document.write( "\"2A=ab+\".....................1\r
\n" ); document.write( "\n" ); document.write( "\"2%2A19=ab+\".....................1\r
\n" ); document.write( "\n" ); document.write( "\"38=%2820-b%29b+\".....................1\r
\n" ); document.write( "\n" ); document.write( "\"38=20b-b%5E2+\".....................1\r
\n" ); document.write( "\n" ); document.write( "\"b%5E2+-20b+%2B+38=0\".....................1.solve using quadratic formula\r
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Solved by pluggable solver: Quadratic Formula
Let's use the quadratic formula to solve for x:

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\n" ); document.write( " Starting with the general quadratic
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\n" ); document.write( " \"ax%5E2%2Bbx%2Bc=0\"
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\n" ); document.write( " the general solution using the quadratic equation is:
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\n" ); document.write( " \"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29\"
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\n" ); document.write( " So lets solve \"x%5E2-20%2Ax%2B38=0\" ( notice \"a=1\", \"b=-20\", and \"c=38\")
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\n" ); document.write( " \"x+=+%28--20+%2B-+sqrt%28+%28-20%29%5E2-4%2A1%2A38+%29%29%2F%282%2A1%29\" Plug in a=1, b=-20, and c=38
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\n" ); document.write( " \"x+=+%2820+%2B-+sqrt%28+%28-20%29%5E2-4%2A1%2A38+%29%29%2F%282%2A1%29\" Negate -20 to get 20
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\n" ); document.write( " \"x+=+%2820+%2B-+sqrt%28+400-4%2A1%2A38+%29%29%2F%282%2A1%29\" Square -20 to get 400 (note: remember when you square -20, you must square the negative as well. This is because \"%28-20%29%5E2=-20%2A-20=400\".)
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\n" ); document.write( " \"x+=+%2820+%2B-+sqrt%28+400%2B-152+%29%29%2F%282%2A1%29\" Multiply \"-4%2A38%2A1\" to get \"-152\"
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\n" ); document.write( " \"x+=+%2820+%2B-+sqrt%28+248+%29%29%2F%282%2A1%29\" Combine like terms in the radicand (everything under the square root)
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\n" ); document.write( " \"x+=+%2820+%2B-+2%2Asqrt%2862%29%29%2F%282%2A1%29\" Simplify the square root (note: If you need help with simplifying the square root, check out this solver)
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\n" ); document.write( " \"x+=+%2820+%2B-+2%2Asqrt%2862%29%29%2F2\" Multiply 2 and 1 to get 2
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\n" ); document.write( " So now the expression breaks down into two parts
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\n" ); document.write( " \"x+=+%2820+%2B+2%2Asqrt%2862%29%29%2F2\" or \"x+=+%2820+-+2%2Asqrt%2862%29%29%2F2\"
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\n" ); document.write( " Now break up the fraction
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\n" ); document.write( " \"x=%2B20%2F2%2B2%2Asqrt%2862%29%2F2\" or \"x=%2B20%2F2-2%2Asqrt%2862%29%2F2\"
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\n" ); document.write( " Simplify
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\n" ); document.write( " \"x=10%2Bsqrt%2862%29\" or \"x=10-sqrt%2862%29\"
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\n" ); document.write( " So the solutions are:
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\n" ); document.write( " \"x=10%2Bsqrt%2862%29\" or \"x=10-sqrt%2862%29\"
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\n" ); document.write( "\n" ); document.write( "\"b1=10+%2B+sqrt%2862%29\" \r
\n" ); document.write( "\n" ); document.write( "\"b1=10+%2B+7.9\" \r
\n" ); document.write( "\n" ); document.write( "\"b1=17.9\" \r
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\n" ); document.write( "\n" ); document.write( "or \"b2=10-7.9\"\r
\n" ); document.write( "\n" ); document.write( "\"b2=2.1\"\r
\n" ); document.write( "\n" ); document.write( "find \"a\"\r
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\n" ); document.write( "\n" ); document.write( "\"a1=+20+-+b\"\r
\n" ); document.write( "\n" ); document.write( "\"a1=+20+-+17.9\"\r
\n" ); document.write( "\n" ); document.write( "\"a1=+2.1\"\r
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\n" ); document.write( "\n" ); document.write( "\"a2=+20+-+b\"\r
\n" ); document.write( "\n" ); document.write( "\"a2=+20+-+2.1\"\r
\n" ); document.write( "\n" ); document.write( "\"a2=+17.9\"\r
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\n" ); document.write( "\n" ); document.write( "now, find \"c\" for \"a1=+2.1\" and \"b1=17.9\" \r
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\n" ); document.write( "\n" ); document.write( "\"c%5E2+=+a%5E2+%2B+b%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "\"c%5E2+=+%282.1%29%5E2+%2B+%2817.9%29%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "\"c%5E2+=+4.41+%2B+320.41\"...round it\r
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\n" ); document.write( "\n" ); document.write( "\"c%5E2+=+4+%2B+320\"\r
\n" ); document.write( "\n" ); document.write( "\"c%5E2+=+324\"\r
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\n" ); document.write( "\n" ); document.write( "\"c=+18\".........\r
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