Answer:
F(f) = 15t + 35 represents the total amount of savings your friend would make in t weeks.
F(d) = 10t + 90 represents the total amount of saving you, darian, would make in t weeks.
When you graph the equations, plugging in different values for t, you can see that the graphs intersect at (11,200). This means that at 11 weeks, both you and your friend have the same amount of money saved up, $200. They will not have the same amount of money in 10 weeks.
