document.write( "Question 1154317: Find the area of the polygons whose vertices are:
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Algebra.Com's Answer #776744 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Since the polygon is convex (has no \"sunk-in\" places), we make this\r\n" );
document.write( "determinant of coordinates of vertices, repeating the first one at\r\n" );
document.write( "the bottom. [It doesn't matter which vertex we start with].\r\n" );
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document.write( "We multiply and add all the \"northwest to southeast\"-diagonals:\r\n" );
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document.write( "(-4)(-4)+(3)(2)+(6)(4)+(1)(2) = 16+6+24+2=48\r\n" );
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document.write( "We multiply and add all the \"northeast to southwest\"-diagonals:\r\n" );
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document.write( "(2)(3)+(-4)(6)+(2)(1)+(4)(-4) = 6-24+2-16=-32\r\n" );
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document.write( "Subtract: 48-(-32) = 48+32 = 80\r\n" );
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document.write( "Do the other one the same way.  Graph it to make sure it is\r\n" );
document.write( "a convex polygon.  [If the polygon is concave, we would break it \r\n" );
document.write( "into convex polygons]. If the area comes out negative, just take\r\n" );
document.write( "the absolute value, making it positive.\r\n" );
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document.write( "Edwin

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