document.write( "Question 686855: Please help me solve\r
\n" ); document.write( "\n" ); document.write( "Monico invests a total of $13,000 in two accounts. The first account earned a rate of return of 15% (after a year). However, the second account suffered a 13% loss in the same time period. At the end of one year, the total amount of money gained was $550.00. How much was invested into each account?\r
\n" ); document.write( "\n" ); document.write( "$________ was invested at 15% and
\n" ); document.write( "$________ was invested at -13%.
\n" ); document.write( "

Algebra.Com's Answer #424929 by KMST(5328)\"\" \"About 
You can put this solution on YOUR website!
$8000 was invested at 15% and
\n" ); document.write( "$5000 was invested at -13%.
\n" ); document.write( "The way to solve it depends on what you are studying
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\n" ); document.write( "IF YOU ARE STUDYING SYSTEMS OF LINEAR EQUATIONS:
\n" ); document.write( "\"x\" = amount (in $) invested at 15%
\n" ); document.write( "\"y\" = amount (in $) invested at -13%
\n" ); document.write( "\"highlight%28x%2By=13000%29\"
\n" ); document.write( "The first account earned $\"0.15x\" (15% of $\"x\")
\n" ); document.write( "The second account \"earned\" a negative amount (lost 13%),
\n" ); document.write( "so the \"earnings\" from the second account (in $) were \"-0.13y\".
\n" ); document.write( "The total earnings (in $) were
\n" ); document.write( "\"highlight%280.15x-0.13y=550%29\"
\n" ); document.write( "Putting both equations together, you get the system of equations
\n" ); document.write( "\"system%28x%2By=13000%2C0.15x-0.13y=550%29\"
\n" ); document.write( "There are many ways to solve such a system,
\n" ); document.write( "but the most intuitive way would be by substitution.
\n" ); document.write( "You could solve the first equation for \"y\":
\n" ); document.write( "\"x%2By=13000\" --> \"y=13000-x\",
\n" ); document.write( "and then substitute the expression \"13000-x\" for \"y\" in the second equation.
\n" ); document.write( "\"0.15x-0.13%2813000-x%29=550\" --> \"0.15x-0.13%2A13000%2B0.13x=550\" --> \"0.15x-1690%2B0.13x=550\" --> \"0.28x-1690=550\" --> \"0.28x=550%2B1690\" --> \"0.28x=2240\" --> \"x=2240%2F0.28\" --> \"highlight%28x=8000%29\"
\n" ); document.write( "Then substitute \"8000\" for \"x\" in \"y=13000-x\" to get
\n" ); document.write( "\"y=13000-8000\" --> \"highlight%28y=5000%29\"
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\n" ); document.write( "IF YOU HAVE NOT STUDIED SYSTEMS OF EQUATIONS:
\n" ); document.write( "\"x\" = amount (in $) invested at 15%
\n" ); document.write( "amount (in $) invested at -13% = \"13000-x\"
\n" ); document.write( "The first account earned $\"0.15x\" (15% of $\"x\")
\n" ); document.write( "The second account \"earned\" a negative amount (lost 13%),
\n" ); document.write( "so the \"earnings\" from the second account (in $) were \"-0.13%2813000-x%29\".
\n" ); document.write( "The total earnings (in $) were
\n" ); document.write( "\"highlight%280.15x-0.13%2813000-x%29=550%29\"
\n" ); document.write( "Now you simplify and solve for \"x\"
\n" ); document.write( "\"0.15x-0.13%2813000-x%29=550\" --> \"0.15x-0.13%2A13000%2B0.13x=550\" --> \"0.15x-1690%2B0.13x=550\" --> \"0.28x-1690=550\" --> \"0.28x=550%2B1690\" --> \"0.28x=2240\" --> \"x=2240%2F0.28\" --> \"highlight%28x=8000%29\"
\n" ); document.write( "Then,
\n" ); document.write( "amount (in $) invested at -13% = \"13000-x=13000-800=highlight%285000%29\"
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