Answer: 8/7
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Work Shown:
Use the slope formula to find the slope of line r
m = (y2-y1)/(x2-x1)
m = (4-11)/(10-2)
m = -7/8
The slope of line r is -7/8
Now we take the negative reciprocal. In other words, we flip the fraction and flip the sign from negative to positive.
Flip the fraction: -7/8 ---> -8/7
Flip the sign: -8/7 ----> +8/7
The slope of line s is 8/7
Note how multiplying the slope of line r (-7/8) and the slope of line s (8/7) yields -1. Multiplying any two perpendicular slopes leads to a product of -1. This is excluding vertical lines as the slope is undefined.