You have $6000 to invest in two stock funds. The first fund pays 5% annual interest and the second account pays 9% annual interest. If after a yea you have made $380 in interest, how much money did you invest in each account?

x = the money invested in the first fund

y = the money invested in the second fund

You have $6000 to invest in two stock funds

x + y = 6000

5% annual interest from x + 9% annual interest from y = $380

0.05x + 0.09y = 380

by solving the system of equations

x + y = 6000

0.05x + 0.09y = 380

we find

x = $4,000

y = $2,000

there were $4,000 invested in the first account and $2,000 invested in the second account.