SOLUTION: Walt made an extra $12,000 last year from a part-time job. He invested part of the money at 7% and the rest at 9%. He made a total of $970 in interest. How much was invested at 7

Question 179363: Walt made an extra $12,000 last year from a part-time job. He invested part of the money at 7% and the rest at 9%. He made a total of $970 in interest. How much was invested at 7%?
Answer by Mathtut(3670) (Show Source): You can put this solution on YOUR website!
let the amount invested at 7% and 9% be x and y respectively
:
x+y=12000............eq 1
.07x+.09y=970.......eq 2
:
rewrite eq 1 to x=12000-y and plug it into eq 2
:
.07(12000-y)+.09y=970
:
840-.07y+.09y=970
:
.02y=130
:
$invested at 9%
:
$amount invested at 7%
RELATED QUESTIONS
walt made an extra $5000 last year from a part-time job. He invested part of the money at (answered by checkley77)

Walt made an extra $12,000 last year from a part time job. He invested part of the money (answered by MissionPossible)

3. Walt made an extra $12,000 last year from a part-time job. He invested part of the... (answered by Earlsdon)

3. Walt made an extra $12,000 last year from a part-time job. He invested part of the... (answered by josmiceli)

Walt made an extra $12,000 last year from a part-time job. He invested part of the money... (answered by checkley77)

Walt made an extra $10,000 last year from a part-time job. He invested part of the money... (answered by ikleyn,greenestamps)

Walt made an extra $5000 last year from a part time job. He invested part of the money at (answered by mananth)

Walt made an extra $10,0000 last year from a part-time job. He invested part of the money (answered by tutorcecilia)

walt made an extra $9000.00 last year from a part time job. he invested part of the money (answered by elima)