document.write( "Question 424851: a retired couple has 170,000 to invest to obtain annual income. they want some of it investing in safe certificstes of deposit yielding 5 percent. the rest they want to invest in AA bonds yielding 11% per year. how much should they invest in each to exactly 15,700 per year? \n" ); document.write( "

Algebra.Com's Answer #296046 by josmiceli(19441) $\"\"$ $\"About$

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Let $\"a\"$ = amount invested @ 5%
\n" ); document.write( "Let $\"b\"$ = amount invested @ 11%
\n" ); document.write( "given:
\n" ); document.write( "(1) $\"a+%2B+b+=+170000\"$
\n" ); document.write( "(2) $\"+.05a+%2B+.11b+=+15700+\"$
\n" ); document.write( "----------------------
\n" ); document.write( "Multiply both sides of (2) by $\"100\"$
\n" ); document.write( "Multiply both sides of (1) by $\"5\"$
\n" ); document.write( "and subtract (1) from (2)
\n" ); document.write( "(2) $\"+5a+%2B+11b+=+1570000+\"$
\n" ); document.write( "(1) $\"+-5a+-+5b+=+-850000+\"$
\n" ); document.write( " $\"+6b+=+720000+\"$
\n" ); document.write( " $\"+b+=+120000+\"$
\n" ); document.write( "and, since
\n" ); document.write( "(1) $\"a+%2B+120000+=+170000\"$
\n" ); document.write( " $\"a+=+50000+\"$
\n" ); document.write( "$50,000 = amount invested @ 5%
\n" ); document.write( "$120,000 = amount invested @ 11% \n" ); document.write( "

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