document.write( "Question 914953: Two lines are parallel if and only if they have the same slop. Complete the equation of the line that is parallel to the line with the equation y=2x+5 and that passes through the point (2,1). \r
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Algebra.Com's Answer #555359 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "She did it using the point-slope form.  I'll do it using\r\n" );
document.write( "only the slope-intercept form y = mx+b\r\n" );
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document.write( "y = 2x+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( "And see that the slope is m=2 and the y-coordinate of the y-intercept\r\n" );
document.write( "is b=5, and so the y-intercept is (0,5), but you only need the slope\r\n" );
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document.write( "The slope of any line parallel to it will also have slope m=2 but\r\n" );
document.write( "will have a different value for b.  So substitute b=2 in\r\n" );
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document.write( " y = mx+b\r\n" );
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document.write( "and get\r\n" );
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document.write( " y = 2x+b\r\n" );
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document.write( "Then since it goes through the point (2,1) we substitute x=2 and y=1\r\n" );
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document.write( " 1 = 2(2)+b\r\n" );
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document.write( " 1 = 4+b\r\n" );
document.write( "-3 = b\r\n" );
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document.write( "Now substitute -3 for b in\r\n" );
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document.write( " y = 2x+b\r\n" );
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document.write( "and get:\r\n" );
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document.write( " y = 2x-3\r\n" );
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document.write( "Edwin
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