Mary is putting money into a checking account. Let  y  represent the total amount of money in the account (in dollars). Let  x  represent the number of weeks Mary has been adding money. Suppose that  x  and  y  are related by the equation  =+75030xy .  Answer the questions below. Note that a change can be an increase or a decrease. For an increase, use a positive number. For a decrease, use a negative number.
What is the change per week in the amount of the account?
what was the starting amount money in the account?