Answer:Let x be the number of hours worked in each caseLet m be the amount of dollars each of them make working in their respective jobsLet b be the amount each of them has saved before working.The equation that represents both cases is a liney = m*x +b (slope intercept form)Maryanny1 = 6($/hour) *x + $9 Carlosy2 = 9($/hour) *x + $3 The slopes represent the amount of dollars each of them can make in an hourWe are basically asked to find the solution of the system of equations(amount of hours = x, and amount of $ obtained = y)Using a graphing tool, we can easily find the intersection of both graphs, which represent the solution for the problem.The solution is Hours of work = x = 2 Amount of $ obtained = y = 21