document.write( "Question 1142081: Find the area of a regular nonagon of side 6cm \n" ); document.write( "

Algebra.Com's Answer #762742 by ikleyn(52866) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "            The \"solution\" by @josgarithmetic is   W R O N G   from its third line to the end.\r
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\n" ); document.write( "\n" ); document.write( "            So, for your safety, simply ignore it . . . \r
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\n" ); document.write( "\n" ); document.write( "            I came to bring the correct solution.\r
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document.write( "There are 9 congruent isosceles triangles covering the area of the nonagon.\r\n" );
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document.write( "The central angle of each triangle is   = 40°.\r\n" );
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document.write( "Each of the base angle of such a triangle is   = 70°.\r\n" );
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document.write( "Half of the base length is 3,  and the height of each isosceles triangle is  h = 3*tan(70°).\r\n" );
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document.write( "Thus the area of each isosceles triangle is  A = .\r\n" );
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document.write( "The area of the nonagon is  9A =  =  = 222.1 cm^2  (approximately).    ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "This quasi- and pseudo- tutor @josgarithmetic is a misfortune of this forum.\r
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\n" ); document.write( "\n" ); document.write( "Having no systematic Math education, he makes errors and provides incorrect solution to each second, third, fourth problem . . . \r
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\n" ); document.write( "\n" ); document.write( "So, be aware when you get \"solutions\" from him.\r
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\n" ); document.write( "\n" ); document.write( "In many (toooooooo many cases) they are wrong.\r
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\n" ); document.write( "\n" ); document.write( "Do not trust him and always wait for the reaction from other tutors . . . \r
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