document.write( "Question 694153: A retired couple has $170,000 to invest to obtain annual income. They want some of it invested in safe Certificates of Deposit yielding 7%. The rest they want to invest in AA bonds yielding 12% per year. How much should they invest in each to realize exactly $17,900 per year? \n" ); document.write( "
Algebra.Com's Answer #427757 by mananth(16946)\"\" \"About 
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CD 7.00% per annum ------------- Amount invested =x
\n" ); document.write( "AA bonds 12.00% per annum ------------ Amount invested = y
\n" ); document.write( " 170000
\n" ); document.write( "Interest----- 17900
\n" ); document.write( "
\n" ); document.write( "CD 7.00% per annum ---x
\n" ); document.write( "AA bonds 12.00% per annum ---y
\n" ); document.write( "Total investment
\n" ); document.write( "x + 1 y= 170000 -------------1
\n" ); document.write( "Interest on both investments
\n" ); document.write( "7.00% x + 12.00% y= 17900
\n" ); document.write( "Multiply by 100
\n" ); document.write( "7 x + 12 y= 1790000.00 --------2
\n" ); document.write( "Multiply (1) by -7
\n" ); document.write( "we get
\n" ); document.write( "-7 x -7 y= -1190000.00
\n" ); document.write( "Add this to (2)
\n" ); document.write( "0 x 5 y= 600000
\n" ); document.write( "divide by 5
\n" ); document.write( " y = 120000
\n" ); document.write( "CD 7.00% $ 50000
\n" ); document.write( "AA bonds 12.00% $ 120000
\n" ); document.write( "
\n" ); document.write( "CHECK
\n" ); document.write( "50000 --------- 7.00% ------- 3500.00
\n" ); document.write( "120000 ------------- 12.00% ------- 14400.00
\n" ); document.write( "Total -------------------- 17900.00
\n" ); document.write( "
\n" ); document.write( "m.ananth@hotmail.ca
\n" ); document.write( " \n" ); document.write( "
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