Let h represent the amount invested at the high interest rate. The equation for the total income is

12%*h + 10%*(15000 - h) = 1600

2%*h + 1500 = 1600 (use the distributive property and collect terms)

2%*h = 100 (subtract 1500)

h = 5000 (multiply by 50)

$5,000 was invested at 12% and $10,000 was invested at 10%.

12%*h + 10%*(15000 - h) = 1600

2%*h + 1500 = 1600 (use the distributive property and collect terms)

2%*h = 100 (subtract 1500)

h = 5000 (multiply by 50)

$5,000 was invested at 12% and $10,000 was invested at 10%.