document.write( "Question 1174543: Nithya has money invested in 3 accounts: Account A earns 3% interest, Account B earns 4%, and Account C earns 5%. The money invested in Account B is 4,000 less than the money in account A. The money invested in Account C is twice the amount in Account A. A total of $1,540 was earned in total interest for the year. What was the total amount of money invested between the 3 accounts at the start of the year?
\n" ); document.write( "I tried this:
\n" ); document.write( "x=account A, y= account B, z= account C
\n" ); document.write( " 0.03x=0.04y+4,000
\n" ); document.write( "0.05z=0.06x
\n" ); document.write( "0.03x+0.04y+0.05z=1540
\n" ); document.write( "But some numbers were negative. What's wrong with my equations? \n" ); document.write( "
Algebra.Com's Answer #799954 by ikleyn(52786)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Account A   x  dollars\r\n" );
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document.write( "Account B   (x-4000)  dollars.\r\n" );
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document.write( "Account C   2x  dollars.\r\n" );
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document.write( "The total interest equation\r\n" );
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document.write( "    0.03x + 0.04*(x-4000) + 0.05*(2x) = 1540   dollars.\r\n" );
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document.write( "Simplify and solve.\r\n" );
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document.write( "I leave it to you.\r\n" );
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\n" ); document.write( "\n" ); document.write( "The lesson to learn from my post is THIS:\r
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        You don't need use 3 unknown.\r
\n" ); document.write( "\n" ); document.write( "        Solve the problem using ONE UNKNOWN, ONLY

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