document.write( "Question 1144139: determine whether a triangle with the given vertices is a right triangle
\n" ); document.write( "D (6,4),E (9,10),F(-2,8)
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Algebra.Com's Answer #765142 by ikleyn(52914) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "The simplest way - requiring minimum calculations - is to calculate three slopes for every side of the triangle\r\n" );
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document.write( "and to check if there are two values of the slopes that are inversely opposite.\r\n" );
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document.write( "If you find such a pair, it means that the corresponding sides are perpendicular.\r\n" );
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document.write( "I will do it for you for the first three points.\r\n" );
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document.write( "slope(DE) =  =  = 2.\r\n" );
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document.write( "Slope(DF) =  =  =  = .\r\n" );
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document.write( "    (!) Stop at this point (!)   \r\n" );
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document.write( "        Slope(DE) has inversely opposite value \"2\" to slope(DF) value of \"  \".\r\n" );
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document.write( "Hence, the side DE is perpendicular to side DF.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Do other cases similarly.\r
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