Atruck can be rented from company a for $90 a day plus $0.30 per mile. company b charges $70 a day plus $0.40 per mile to rent the same truck. how many miles must be driven in a day to make the rental cost for company a a better deal than company b's?

At the beginning of the year, adrian's savings account balance was \$28$28. each week, he deposits another \$15$15 into that account, and he doesn't spend any of his savings. is his savings account balance proportional to the number of weeks since the start of the year?