This is a rational function where f(x) = (a(x)+b)/(c(x)+d)
a affects the horizontal asymptote of the graph. As a increases the vertical asymptote shifts up.
b affects the spacing of the graph to the asymptotes. As |b| increases, the spacing between the graph and asymptote increases.
c affects both the horizontal and vertical asymptote. It causes a stretch/shrink depending on its magnitude.
d affects the vertical asymptote. As d increases the vertical asymptote shifts to the left.