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The slope of a line between (a, b) and (x, F(x)) is [tex]\frac{F(x)- b}{x- a}. Here, a= 4, b= 1/3, and [tex]F(x)= \frac{-1}{x-7} so that gives . To simplify that, I recommend multiplying both numerator and denominator by 3(x- 7).Let (x, F(x)) be a point on the graph of f with x cannot equal 4. The slope of the (secant) line joining the two points (4, 1/3) and (x,F(x)) can be simplified to the form A/x-7, where A is a constant. Find A.