Question 676458
Find the slope of a line perpendicular to the line through the points (2,4) and (-12,8)

Solution:

Two points given are
P = (2, 4) = (x1, y1)
Q = (-12, 8) = (x2, y2)

Slope of the line PQ
m1 = y2-y1/x2-x1 = 8 - 4/-12 - 2 = 4/-14 = -2/7

There fore

m1 = -2/7

The slope of the line perpendicular to the given line PQ will be the negative reciprocal of the slope of the line PQ

i.e.

m2 = -1/m1 
(m2 is the slope of the line perpendicular to the slope of the given line PQ)

m2 = -1/-2/7

or

m2 = 7/2

This is the required slope of the line perpendicular to the line through the points (2, 4) and (-12, 8).

Hope the answer your question

Regards,

Khurshidi
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