SOLUTION: Roberto invested some money at 8%, and then invested $3000 more than twice this amount at 9%. HIs total annual income from the two investments was $3130. How much was invested at 9

Question 315583: Roberto invested some money at 8%, and then invested $3000 more than twice this amount at 9%. HIs total annual income from the two investments was $3130. How much was invested at 9%? A)$25,000 B)$2500 C)$22,000 D)$9000
I tried by setting my values as follows:
X=.08X
Y=.09Y+3000(.08X)

Answer by Fombitz(32388) (Show Source): You can put this solution on YOUR website!
OK, first name your variables.
Let be the amount at 8%, the amount at 9%.
You know the relationship between A and B.
1.
Also you know the total interest from both of the investments.

Multiply both side by 100 to get rid of decimals.

Substitute eq. 1 into eq. 2 and solve for A.

Then from eq. 1,

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