word problem

[scal]

Elena receives $212 per year in simple interest from three investments totaling $2500. Part is invested at 7%, part at 8%, and part at 9%. There is 1100 more invested at 9% than at 8%. Find the amount invested at each rate.

 

[jsterkel]

Please show your work, and where you are having trouble.

 

[scal]

Elena receives $212 per year in simple interest from three investments totaling $2500. Part is invested at 7%, part at 8%, and part at 9%. There is 1100 more invested at 9% than at 8%. Find the amount invested at each rate.

Think I got it. Answer checks out now. Just an oversight thanks.

x+y+z=2500

.07x+.08y+.09z=212

y +1100= z
so y -z = -1100

1 1 1 2500
0 .01 .02 212
0 1 -1 -1100

 

[mmm4444bot]

1 1 1 2500
0 .01 .02 212
0 1 -1 -1100

This matrix is not correct.