document.write( "Question 786385: Jen invested $7,500 in two bank accounts, one paying 4% simple interest, and the other paying 6%. If her annual interest from the two accounts is $420, how much did she invest at 6%? \n" ); document.write( "
Algebra.Com's Answer #477875 by mananth(16946)\"\" \"About 
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Part I 4.00% per annum ------------- Amount invested =x
\n" ); document.write( "Part II 6.00% per annum ------------ Amount invested = y
\n" ); document.write( " 7500
\n" ); document.write( "Interest----- 420.00
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\n" ); document.write( "Part I 4.00% per annum ---x
\n" ); document.write( "Part II 6.00% per annum ---y
\n" ); document.write( "Total investment
\n" ); document.write( "x + 1 y= 7500 -------------1
\n" ); document.write( "Interest on both investments
\n" ); document.write( "4.00% x + 6.00% y= 420
\n" ); document.write( "Multiply by 100
\n" ); document.write( "4 x + 6 y= 42000.00 --------2
\n" ); document.write( "Multiply (1) by -4
\n" ); document.write( "we get
\n" ); document.write( "-4 x -4 y= -30000.00
\n" ); document.write( "Add this to (2)
\n" ); document.write( "0 x 2 y= 12000
\n" ); document.write( "divide by 2
\n" ); document.write( " y = 6000 - x)
\n" ); document.write( "Part I 4.00% $ 1500
\n" ); document.write( "Part II 6.00% $ 6000
\n" ); document.write( "
\n" ); document.write( "CHECK
\n" ); document.write( "1500 --------- 4.00% ------- 60.00
\n" ); document.write( "6000 ------------- 6.00% ------- 360.00
\n" ); document.write( "Total -------------------- 420.00
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\n" ); document.write( "m.ananth@hotmail.ca
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