document.write( "Question 864353: Merry had $20,000 to invest. She invested part of this money in bonds paying 10% annual simple interest and the rest of the money in a savings account giving 5% annual interest. At the end of the year, she received $1,800 as extra income. How much money did merry place in the savings account. \n" ); document.write( "
Algebra.Com's Answer #520935 by mananth(16946)\"\" \"About 
You can put this solution on YOUR website!
Part I 10.00% per annum ------------- Amount invested =x
\n" ); document.write( "Part II 5.00% per annum ------------ Amount invested = y
\n" ); document.write( " 20000
\n" ); document.write( "Interest----- 1800.00
\n" ); document.write( "
\n" ); document.write( "Part I 10.00% per annum ---x
\n" ); document.write( "Part II 5.00% per annum ---y
\n" ); document.write( "Total investment
\n" ); document.write( "x + 1 y= 20000 -------------1
\n" ); document.write( "Interest on both investments
\n" ); document.write( "10.00% x + 5.00% y= 1800
\n" ); document.write( "Multiply by 100
\n" ); document.write( "10 x + 5 y= 180000.00 --------2
\n" ); document.write( "Multiply (1) by -10
\n" ); document.write( "we get
\n" ); document.write( "-10 x -10 y= -200000.00
\n" ); document.write( "Add this to (2)
\n" ); document.write( "0 x -5 y= -20000
\n" ); document.write( "divide by -5
\n" ); document.write( " y = 4000
\n" ); document.write( "Part I 10.00% $ 16000
\n" ); document.write( "Part II 5.00% $ 4000
\n" ); document.write( "
\n" ); document.write( "CHECK
\n" ); document.write( "16000 --------- 10.00% ------- 1600.00
\n" ); document.write( "4000 ------------- 5.00% ------- 200.00
\n" ); document.write( "Total -------------------- 1800.00
\n" ); document.write( "
\n" ); document.write( "m.ananth@hotmail.ca
\n" ); document.write( "
\n" ); document.write( "
\n" );