document.write( "Question 82103: determine which two equations represent parallel lines
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Algebra.Com's Answer #58838 by Edwin McCravy(20055)\"\" \"About 
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document.write( "determine which two equations represent parallel lines\r\n" );
document.write( "y=5/8x+3\r\n" );
document.write( "y=-8/5x-8\r\n" );
document.write( "y=3x+11\r\n" );
document.write( "y=3x-3\r\n" );
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document.write( "Each of those equations is in the slope-intercept form: \r\n" );
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document.write( "                y = mx + b\r\n" );
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document.write( "where m represents the slope and (0,b) is the y-intercept.\r\n" );
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document.write( "Lines are parallel when and only when they have the same slope.\r\n" );
document.write( "The slope is m, the coefficient of x.\r\n" );
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document.write( "Only the last two, y = 3x + 11 and y = 3x - 3 have the same\r\n" );
document.write( "coefficient of x, or value of m, namely 3, and this is their \r\n" );
document.write( "slope.  So they are the only ones which are parallel. \r\n" );
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document.write( "Incidentally, the first two are perpendicular because they have\r\n" );
document.write( "slopes which are negative reciprocals of each other, that is,\r\n" );
document.write( "5/8 and -8/5\r\n" );
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document.write( "Edwin

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