Marshall's mistake lies in his conclusion about the growth rates of the functions as x increases. The correct response is:
Marshall is only considering a small portion of the domains of the functions. If he went farther to the right on the graph, he would observe that the growth rate of f(x)=6⋅1.5x eventually surpasses the growth rate of g(x)=5x+10 for large values of x.
This statement highlights that while g(x) may initially grow faster than f(x) for certain values of x, the exponential growth rate of f(x) will eventually outpace the linear growth rate of g(x) as x increases.