You invested ​$27,000 in two accounts paying 2% and 3% annual​ interest, respectively.If the total interest earned for the year was $ 800, how much was invested at each​ rate?

Answer 1

x + y = 27000

.02x + .03 y = 800

Interest = amount times rate times time

Usually people multiply by 100 to get rid of the decimals.
x + y = 27000
2x + 3y = 80000

Multiply the first equation by -2

-2x-2y =-54000
2x + 3y = 80000
add the two equations together to solve for y which tells you how much was invested at 3%.

Subtract that from the 27000 to find out how much was invested at 2%