document.write( "Question 738553: I need math help :/ Stacey's student loan totaled $12000. One of her loans was at 6.5% simple interest and the other at 7.2%. After one year, Stacey owed 811.50 in interest. What was the amount of each loan?I don't understand! \n" ); document.write( "
Algebra.Com's Answer #450858 by mananth(16946)\"\" \"About 
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Part I 6.50% per annum ------------- Amount invested =x
\n" ); document.write( "Part II 7.20% per annum ------------ Amount invested = y
\n" ); document.write( " 12000
\n" ); document.write( "Interest----- 811.50 for one year
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\n" ); document.write( "Total investment
\n" ); document.write( "x + y= 12000 -------------1
\n" ); document.write( "Interest on both investments
\n" ); document.write( "6.50% x + 7.20% y= 811.5
\n" ); document.write( "Multiply by 100
\n" ); document.write( "6.5 x + 7.2 y= 81150.00 --------2
\n" ); document.write( "Multiply (1) by -6.5
\n" ); document.write( "we get
\n" ); document.write( "-6.5 x -6.5 y= -78000.00
\n" ); document.write( "Add this to (2)
\n" ); document.write( "0 x 0.7 y= 3150
\n" ); document.write( "divide by 0.7
\n" ); document.write( " y = 4500
\n" ); document.write( "Part I 6.50% $ 7500
\n" ); document.write( "Part II 7.20% $ 4500
\n" ); document.write( "
\n" ); document.write( "CHECK
\n" ); document.write( "7500 --------- 6.50% ------- 487.50
\n" ); document.write( "4500 ------------- 7.20% ------- 324.00
\n" ); document.write( "Total -------------------- 811.50
\n" ); document.write( "
\n" ); document.write( "m.ananth@hotmail.ca
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