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You can put this solution on YOUR website!
parallel lines = same slope
\n" ); document.write( "perpendicular lines = negative reciprocal slopes
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document.write( "since slope m = 2 the perpendicular slope will be -1/2
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document.write( "therefore all lines where y = -1/2x + b will be perpendicular
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document.write( "from here one could use a couple different line formulas. I'll start with the slope formula (since I have that memorized)
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document.write( "m = (y2 - y1)/(x2 - x1); which is easily changed to the point-slope formula by multiplying both sides by (x2 - x1):
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document.write( "(x2 - x1)m = (y2 - y1), or more simply: (x - x1)m = (y - y1).
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document.write( "The point-slope formula, as its name suggests, finds the equation of a line when both a point on the line and the slope are known.
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document.write( "The \"point\" of this point-slope formula is (3,4) and the slope is -1/2. Therefore, substituting in:
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document.write( "(x - 3)(-1/2) = (y - 4)
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document.write( "distribute the -1/2
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document.write( "-1/2x + 1.5 = y - 4
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document.write( "add 4 to both sides
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document.write( "-1/2x + 5.5 = y
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document.write( "and that's the equation:
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document.write( "y = -1/2x + 5.5\r
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