precalculus
posted by zana .
$100,000 is divided into two investments with annual returns of 4% and 7.5%. find the amount invested at the lower rate if the total income at the end of the year is $5050?

work with the principal and the interest.
x * 0.04 + (100000x) * 0.075 = 5050
.04x + 7500  .075x = 5050
.035x = 2450
x = 70000
70000 * .04 + 30000 * .075 = 5050