the inverse of function f(x) = (2x-2)/(x-5) is written in the form of $f^{-1}(x)=\dfrac{ax+b}{cx+d}$, where a, b, c, and d are all real numbers. Find a/c.
y = (2x - 2) / (x - 5) get x by itself
y (x - 5) = (2x -2)
xy - 5y = 2x - 2
xy - 2x = 5y - 2
x ( y -2) = (5y -2)
x = (5y -2) / ( y -2) exchange x, y
y = (5x -2) / ( x - 2) = f-1(x)
a = 5 c =1
a / c = 5 / 1 = 5
