document.write( "Question 1116696: What is the area of triangle ABC if a=5ft, b=6ft, and c=7ft
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Algebra.Com's Answer #731608 by ikleyn(52806)\"\" \"About 
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document.write( "Use the Heron's formula for the area of a triangle:\r\n" );
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document.write( "    Area = \"sqrt%28s%28s-a%29%28s-b%29%28s-c%29%29\" = ,\r\n" );
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document.write( "where  \"a\",  \"b\"  and  \"c\"  are the measures of a triangle sides,   and  \"s\"  is the triangle semi-perimeter:  \"s\" = \"%28a+%2B+b+%2B+c%29%2F2\". \r\n" );
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document.write( "In your case the perimeter = 5 + 6 + 7 = 18ft;  sem-perimeter s = \"18%2F2\" = 9 ft,\r\n" );
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document.write( "and the formula works in this way \r\n" );
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document.write( "    Area = \"sqrt%289%2A%289-5%29%2A%289-6%29%2A%289-7%29%29\" = \"sqrt%289%2A4%2A3%2A2%29\" = \"3%2A2%2Asqrt%286%29\" = 14.7 square ft.\r\n" );
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\n" ); document.write( "\n" ); document.write( "On the Heron's formula see the lessons\r
\n" ); document.write( "\n" ); document.write( "    - Proof of the Heron's formula for the area of a triangle \r
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