find the value of r so that the line that passes through each pair of points has the given slope

Question

(r,4), (7,1), m=

Answer 1

You didn't state the slope.

what ever it is ...

(4-1)/(r-7) = m
m(r-7) = 3
mr - 7m = 3
mr = 3 + 7m
r = (3+7m)/m
so whatever m is, just plug it into that expression.

or

suppose the given m = 3/4

then (4-1)/(r-7) = 3/4
3r - 21 = 12
3r = 33
r = 11

Use the above method with your given slope, should be easy.