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Which of the following equations represents a line that is perpendicular to the line that passes through the points below?

-7,-3 and -5, 7

User Dibery
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1 Answer

3 votes
A line that's perpendicular would have a slope that the negative reciprocal of the line in the question
1. use the points to find the slope
(y1-y2)/(x1-x2)
=(-3-7)/(-7+5) (it's +5 because --5=+5)
=-10/-2
-5
slope of the line is -5
2. The negative reciprocal is basically flipping over a fraction (3/4 would become 4/3) and then multiplying it by -1 (4/3 would become -4/3)
Because -5 is really -5/1 you would flip it to -1/5 then multiple by -1 to equal 1/5.
3. Now we just need any line that has a slope of 1/5
y=mx+b where m=1/5 and b is whatever number you want
y=1/5x+8
y=1/5x-193748
y=1/5x-103595
All these are right answers just pick your favourite number for b
User Putri
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7.6k points