document.write( "Question 143318: Walt made an extra $9000 last year from a part-time job. He invested part of the
\n" ); document.write( " money at a 9% annual rate of interest, and the rest at an 8% annual rate of
\n" ); document.write( " interest. At the end of the year, he made a total of $770 in interest. How much was invested at 8%? \n" ); document.write( "
Algebra.Com's Answer #104321 by ankor@dixie-net.com(22740)\"\" \"About 
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Walt made an extra $9000 last year from a part-time job. He invested part of the money at a 9% annual rate of interest, and the rest at an 8% annual rate of interest. At the end of the year, he made a total of $770 in interest. How much was invested at 8%?
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\n" ); document.write( "Let x = amt invested at 8%
\n" ); document.write( "It said the total amt was 9000, therefore:
\n" ); document.write( "(9000-x) = amt invested at 9%
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\n" ); document.write( "An equation showing the sum of the two interest amts to be $770
\n" ); document.write( ".08x + .09(9000-x) = 770
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\n" ); document.write( ".08x + 810 - .09x = 770
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\n" ); document.write( ".08x - .09x = 770 - 810
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\n" ); document.write( "-.01x = -40
\n" ); document.write( "x = \"%28-40%29%2F%28-.01%29\"
\n" ); document.write( "x = $4000 invested at 8%
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\n" ); document.write( "Check solution (5000 invested at 9%)
\n" ); document.write( ".08(4000) + .09(5000) =
\n" ); document.write( "320 + 450 = 770 \n" ); document.write( "
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