Ana María had $28,000 to invest. She divided the money into three different accounts. At the end of the year, she had made $1,160 in interest. The annual yield on each of the three accounts was 3.5%, 4.25% and 4.75%. The amount of money in the 4.75% account was 75% of the amount of money in the 3.5% account. Define variables and write systems of equations to represent the situation. Solve the system to determine how much was put into each account.