SOLUTION: determine the value of r so that the line through (5,20) and (7,r) has a slope of m=-1/2

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Question 640146: determine the value of r so that the line through (5,20) and (7,r) has a slope of m=-1/2
Found 2 solutions by reviewermath, lwsshak3:
Answer by reviewermath(1029) About Me  (Show Source):
Answer by lwsshak3(11628) About Me  (Show Source):
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determine the value of r so that the line through (5,20) and (7,r) has a slope of m=-1/2
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slope=∆y/∆x=change in y/change in x
using coordinates of given points.
m=(r-20)/(7-5)=(r-20)/2=-1/2
r-20=-1
r=19