document.write( "Question 37344: How do i calculate the area of a piece of land with unequal dimensions, such as a trapezium and scalene triangle \n" ); document.write( "
Algebra.Com's Answer #22980 by AnlytcPhil(1806)\"\" \"About 
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If it is a scalene triangle, and you know only the length of the sides, you\r\n" );
document.write( "can use Heron's (or Hero's) formula:\r\n" );
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document.write( "Suppose the sides are a, b, and c.\r\n" );
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document.write( "Then find the perimeter, P = a + b + c\r\n" );
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document.write( "Then find the semi-perimeter, s, by taking 1/2 of the perimeter P.\r\n" );
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document.write( "Then Area = Ös(s - a)(s - b)(s - c)\r\n" );
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document.write( "Whereas a triangle is a rigid, (that is, only the three sides need be\r\n" );
document.write( "known to determine the area), a trapezium is not.\r\n" );
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document.write( "So if it is a trapezium, or any quadrilateral other than a rectangle\r\n" );
document.write( "(whether any two sides are parallel or not) then you must measure one\r\n" );
document.write( "of the diagonals in order to calculate the area.  The diagonal will\r\n" );
document.write( "then divide the quadrilateral into two triangles, each of whose area\r\n" );
document.write( "can be calculated using Heron's formula above.  Then the two areas can\r\n" );
document.write( "be added to give the area of the quadrilateral.\r\n" );
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document.write( "Edwin\r\n" );
document.write( "AnlytcPhil@aol.com
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