SOLUTION: What is the value of c such that the points (-3,5) and (8,c) lie on a line with slope -1/5?

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Question 822107: What is the value of c such that the points (-3,5) and (8,c) lie on a line with slope -1/5?
Answer by LinnW(1048) About Me  (Show Source):
You can put this solution on YOUR website!
The first step is to find the equation
with slope -1/5 through the point (-3,5)
Use y = mx + b as a pattern
5 = (-1/5)(-3) + b
5 = -3/5 + b
add 3/5 to each side.
5 3/5 = b
So our equation
y = (-1/5)x + 5 3/5
Now to find c in the point (8,c) we
substitute 8 for x.
y = (-1/5)(8) + 5 3/5
y = -8/5 + 5 3/5
y = 4
So c = 4
and the point is (8,4).