Precalculus
posted by Joanna .
invests 7000 for 1 year part at 5% part at 11% and the remainder at 13% total amount of income from these investments was $774. The amount of money invested at 13% was $1200 more than the amounts invested at 5% and 11% combined find the amount invested at each rate

if x at 5%, y at 11% and z at 13%,
x+y+z = 7000
.05x + .11y + .13z = 774.00
z = 1200+x+y
(x,y,z) = (1300,1600,4100)