SOLUTION: 1)If I invest $x at 8% and $y at 9% my annual income is $430. Had I invested $x at 9% and $y at 8% my annual income would have been $420. Find x and y.'
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-> SOLUTION: 1)If I invest $x at 8% and $y at 9% my annual income is $430. Had I invested $x at 9% and $y at 8% my annual income would have been $420. Find x and y.'
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Question 852790: 1)If I invest $x at 8% and $y at 9% my annual income is $430. Had I invested $x at 9% and $y at 8% my annual income would have been $420. Find x and y.' Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! If I invest $x at 8% and $y at 9% my annual income is $430.
Had I invested $x at 9% and $y at 8% my annual income would have been $420.
Find x and y.
.08x + .09y = 430
and
.09x + .08y = 420
Get rid of those annoying decimals, mult both by 100
8x + 9y = 43000
9x + 8y = 42000
:
use elimination here mult the 1st eq by 9, the 2nd eq by 8
72x + 81y = 387000
72x + 64y = 336000
---------------------Subtraction eliminates x find y
0 + 17y = 51000
y = 51000/17
y = $3000
:
Find x using 8x + 9y = 430000, replace y with 3000
8x + 9(3000) = 43000
8x + 27000 = 43000
8y = 43000-27000
8y = 16000
y = 16000/8
y = $2000
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You should confirm these solutions in the original equations
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