document.write( "Question 1112513: Emily invested a total of $12,000 in two savings accounts. One account earns 5% simple interest and the other earns 8% simple interest. Find the amount invested in each account account if she receives a total of $840 interest after 1 year \n" ); document.write( "

Algebra.Com's Answer #727568 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "Let x be an amount invested at 5%, in dollars.\r\n" );
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document.write( "Then the amount invested at 8% is the rest (12000-x) dollars.\r\n" );
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document.write( "Your basic equation is THIS:\r\n" );
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document.write( "interest + interest       = total interest\r\n" );
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document.write( "0.05*x   + 0.08*(12000-x) = 840.\r\n" );
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document.write( "0.05x + 0.08*12000 - 0.08x = 840\r\n" );
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document.write( "-0.03x = 840 - 0.08*12000 = -120  ====>  x =  = 4000.\r\n" );
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document.write( "Answer.  $4000 was invested at 5%  and the rest  12000 - 4000 = 8000 dollars was invested at 8%.\r\n" );
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document.write( "Check.   0.05*4000 + 0.08*8000 =  840 dollars.   ! Correct !\r\n" );
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\n" ); document.write( "To see many other similar solved problems on investment, look into the lesson\r
\n" ); document.write( "\n" ); document.write( " - Using systems of equations to solve problems on investment\r
\n" ); document.write( "\n" ); document.write( "in this site.\r
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\n" ); document.write( "\n" ); document.write( "You will find there different approaches (using one equation or a system of two equations in two unknowns), as well as
\n" ); document.write( "different methods of solution to the equations (Substitution, Elimination).\r
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\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook in ALGEBRA-I in this site\r
\n" ); document.write( "\n" ); document.write( " - ALGEBRA-I - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lesson is the part of this online textbook under the topic \"Systems of two linear equations in two unknowns\".\r
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\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Save the link to this online textbook together with its description\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-I
\n" ); document.write( "https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson\r
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\n" ); document.write( "\n" ); document.write( "to your archive and use it when it is needed.\r
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