Question 274019
Slope is (change in y)/(change in x) between 2 points on
a straight line. The line must be straight to work.
You have the points
P1(8,3) and
P2(4,1)
The formula is {{{m = (y[2] - y[1])/(x[2] - x[1])}}}
where {{{m}}} is slope
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plugging in coordinates from your points,
m = (change in y)/(change in x)
{{{m = (1 - 3)/(4 - 8)}}}
{{{m = -2/-4}}}
{{{m = 1/2}}}
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Any line parallel to any line with slope = 1/2
will also have slope = 1/2
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The formula for finding a slope perpendicular
to a given slope is:
{{{m[p] = -(1/m)}}}, so for your points,
{{{m[p] = -(1/(1/2))}}}
{{{m[p] = -2}}}
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Any line perpendicular to any line with slope = 1/2
will have slope = -2