Question 111443
Tell whether the line that passes through the two given points is parallel or perpendicular  or neither to a line with a slope of -2.

(5,3),(7,-1)
(5,3),(7,-3)
(5,3),(7,4)
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Parallel lines have the same slope
Perpendicular lines have negative reciprocal slope
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Use the point-slope formula;
{{{m=(Y2-Y1)/(X2-X1)}}}
{{{m=(-1-3)/(7-5)}}}
{{{m=-4/2=-2}}}
Same slope, line is parallel
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{{{m=(-3-3)/(7-5)}}}
{{{m=-6/2=-3}}}
neither
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{{{m=(4-3)/(7-5)}}}
{{{m=1/2}}}
Negative reciprocal of -2, so line is perpendicular
:)