SOLUTION: Find the slope of any line perpendicular to the line through points (8, 9) and (4, 8)

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Question 82860: Find the slope of any line perpendicular to the line through points (8, 9) and (4, 8)
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
First lets find the slope of the line going through (8, 9) and (4, 8)

Solved by pluggable solver: Finding the slope


Slope of the line through the points (8, 9) and (4, 8)



m+=+%28y%5B2%5D+-+y%5B1%5D%29%2F%28x%5B2%5D+-+x%5B1%5D%29


m+=+%288+-+9%29%2F%284+-+8%29


m+=+%28-1%29%2F%28-4%29


m+=+1%2F4



Answer: Slope is m+=+1%2F4




Remember, perpendicular slopes are always the negative reciprocal of each other. In other words we have

m%5Bp%5D=-1%2Fm where m%5Bp%5D is the perpendicular slope

so plug in the slope we solved for to find the perpendicular slope:

m%5Bp%5D=-1%2F%281%2F4%29=-%281%2F1%29%2A%284%2F1%29=4 Plug in m=2

So the perpendicular slope is -4