Answer: Choice A) 8/3
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Explanation:
Use the slope formula to find the slope of the given line through those two points (-3, 4) and (5, 1)
m = (y2-y1)/(x2-x1)
m = (1 - 4)/(5 - (-3) )
m = (1-4)/(5+3)
m = -3/8
The line shown has a slope of -3/8
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We do two things from here:
- flip the fraction
- flip the sign
That will have -3/8 turn into +8/3 or simply 8/3 which is the perpendicular slope. That's why the answer is choice A.
Multiplying the original slope -3/8 with the perpendicular slope 8/3 will lead to -1. This is true of any perpendicular pair of lines, as long as neither line is vertical.
