document.write( "Question 345340: a total of $8000 is invested. part at 7% and the remainder at 15%. how much is invested at each rate if theannual intrest is 680$? \n" ); document.write( "
Algebra.Com's Answer #247009 by Fombitz(32388)\"\" \"About 
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Let A be the amount invested at 7%, B the amount at 15%.
\n" ); document.write( "1.\"A%2BB=8000\"
\n" ); document.write( "2.\"7A%2B15B=68000\"
\n" ); document.write( "Multiply eq. 1 by (-7) and add to eq. 2,
\n" ); document.write( "\"-7A-7B%2B7A%2B15B=-56000%2B68000\"
\n" ); document.write( "\"8B=12000\"
\n" ); document.write( "\"highlight%28B=1500%29\"
\n" ); document.write( "Then from eq. 1,
\n" ); document.write( "\"A%2B1500=8000\"
\n" ); document.write( "\"highlight%28A=6500%29\"
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