you invested $6000 in two accounts paying 7% and 9% annual interest. at the end of the year, the total interest from these investments was $510. how much was invested at each rate?

Respuesta :

Answer:

  • $1500 at 7%
  • $4500 at 9%

Step-by-step explanation:

Let x represent the amount invested at 9%. Then 6000-x is the amount invested at 7%, and the total interest earned is ...

  0.09x + 0.07(6000-x) = 510

  0.02x + 420 = 510 . . . simplify

  0.02x = 90 . . . . . . . . . subtract 420; next, divide by 0.02

  x = 4500 . . . . . . . . . . . the amount invested at 9%

  6000-x = 1500 . . . . . .the amount invested at 7%

$4500 was invested at 9%; $1500 was invested at 7%.