Katie invested a total of $6000 part at 3% simple interest and part at 4% simple interest at the end of one year the investment had earned $216 interest how much was invested at each rate?

Step-by-step explanation:

Let x represent the amount invested at 4% (the higher rate). Then the amount invested at 3% is (6000-x), and the total interest earned is ...

  0.04x + 0.03(6000 -x) = 216

  0.01x +180 = 216 . . . . simpilfy

  0.01x = 36 . . . . . . . . subtract 180

  x = 3600 . . . . . . . . multiply by 100

  6000-x = 2400

Katie invested $3600 at 4% and $2400 at 3%.

what's that

none of the above.

for one of the equations to be used in the process, there has to be a term in the equation since squared is .

since there is only a term in the first equation, we cannot derive a from completing the square.

solving with completing the square