You invested ​$22,000 in two accounts paying 2% and 6% annual​ interest, respectively. If the total interest earned for the year was $720 how much was invested at each​ rate?

Answer 1

x dollars in 2%, then (22000 - x) in 6%.

0.02x + 0.06(22000 - x) = 720; - 0.04x = 720 - 1320; - 0.04x = - 600; x = $15000 (2% account)

22000 - x = 22000 - 15000 = %7000 (6% account)