document.write( "Question 84357: Determine whether each pair of lines is parallel, perpendicular, or neither.\r
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Algebra.Com's Answer #60757 by Edwin McCravy(20060) $\"\"$ $\"About$

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Determine whether each pair of lines is parallel, \r\n" );
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document.write( "5x-y=8    and    5y= -x+3\r\n" );
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document.write( "If their slopes are equal they are parallel\r\n" );
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document.write( "If the slopes of one is  the reciprocal of the slope of the\r\n" );
document.write( "other with the sign changed, they are perpendicular.\r\n" );
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document.write( "Solve each for y to get them into the slopeintercept form:\r\n" );
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document.write( "Solving the first one for y\r\n" );
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document.write( "5x - y = 8          \r\n" );
document.write( "    -y = -5x + 8     (added -5x to both sides\r\n" );
document.write( "     y = 5x - 8      {divided through by -1\r\n" );
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document.write( "Compare that to\r\n" );
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document.write( "     y = mx + b\r\n" );
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document.write( "m = 5, b = -8 \r\n" );
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document.write( "This means the slope, m, is 5, and the y-intercept is (0,-8)\r\n" );
document.write( "We don't need the y-intercept in this problem, because all \r\n" );
document.write( "we need is the slope, which is 5.\r\n" );
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document.write( "Solving the second one for y\r\n" );
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document.write( "    5y = -x + 3\r\n" );
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document.write( "     y =   divided through by 5\r\n" );
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document.write( "     Compare that to\r\n" );
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document.write( "     y = mx + b\r\n" );
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document.write( "m = -1/5, b =  \r\n" );
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document.write( "This means the slope, m, is -1/5, and the y-intercept is (0,)\r\n" );
document.write( "We don't need the y-intercept in this problem, because all \r\n" );
document.write( "we need is the slope, which is .\r\n" );
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document.write( "They are perpendicular because -1/5 is the reciprocal of 5 with the\r\n" );
document.write( "sign changed.\r\n" );
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document.write( "Edwin

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