document.write( "Question 179363: Walt made an extra $12,000 last year from a part-time job. He invested part of the money at 7% and the rest at 9%. He made a total of $970 in interest. How much was invested at 7%? \n" ); document.write( "

Algebra.Com's Answer #134270 by Mathtut(3670) $\"\"$ $\"About$

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let the amount invested at 7% and 9% be x and y respectively
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\n" ); document.write( "x+y=12000............eq 1
\n" ); document.write( ".07x+.09y=970.......eq 2
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\n" ); document.write( "rewrite eq 1 to x=12000-y and plug it into eq 2
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\n" ); document.write( ".07(12000-y)+.09y=970
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\n" ); document.write( "840-.07y+.09y=970
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\n" ); document.write( ".02y=130
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\n" ); document.write( "$ $\"highlight%28y=6500%29\"$ invested at 9%
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\n" ); document.write( "$ $\"highlight%28x=12000-6500=5500%29\"$ amount invested at 7% \n" ); document.write( "

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