document.write( "Question 529205: John invested $8000 for one year, part at 8% interest and the rest at 10%. If John earned $700 in interest, how much is in each account? \n" ); document.write( "

Algebra.Com's Answer #349524 by josmiceli(19441) $\"\"$ $\"About$

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Let $\"+a+\"$ = amount invested @ 8%
\n" ); document.write( "Let $\"+b+\"$ = amount invested @ 10%
\n" ); document.write( "given:
\n" ); document.write( "(1) $\"+a+%2B+b+=+8000+\"$
\n" ); document.write( "(2) $\"+.08a+%2B+.1b+=+700+\"$
\n" ); document.write( "-----------------
\n" ); document.write( "(2) $\"+8a+%2B+10b+=+70000+\"$
\n" ); document.write( "(2) $\"+4a+%2B+5b+=+35000+\"$
\n" ); document.write( "Multiply both sides of (1) by $\"4\"$
\n" ); document.write( "and subtract (1) from (2)
\n" ); document.write( "(2) $\"+4a+%2B+5b+=+35000+\"$
\n" ); document.write( "(1) $\"+-4a+-+4b+=+-32000+\"$
\n" ); document.write( " $\"+b+=+3000+\"$
\n" ); document.write( "and, since
\n" ); document.write( "(1) $\"+a+%2B+b+=+8000+\"$
\n" ); document.write( "(1) $\"+a+=+8000+-+3000+\"$
\n" ); document.write( "(1) $\"+a+=+5000+\"$
\n" ); document.write( "$5,000 is the amount invested @ 8%
\n" ); document.write( "$3,000 is the amount invested @ 10%
\n" ); document.write( "check answer:
\n" ); document.write( "(2) $\"+.08a+%2B+.1b+=+700+\"$
\n" ); document.write( "(2) $\"+.08%2A5000+%2B+.1%2A3000+=+700+\"$
\n" ); document.write( "(2) $\"+400+%2B+300+=+700+\"$
\n" ); document.write( "(2) $\"+700+=+700+\"$
\n" ); document.write( "OK \n" ); document.write( "

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