document.write( "Question 1104019: Blake is working his way through school. He works two part-time jobs for a total of
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Algebra.Com's Answer #718750 by ikleyn(52781) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "     x +      y = 32        (1)    (hours, counting Blake's working hours)\r\n" );
document.write( "6.10*x + 7.20*y = 211.70    (2)    (dollars, counting his earnings)\r\n" );
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document.write( "Multiply eq(1) by 6.10 (both sides).  The modified (and equivalent) system is THIS:\r\n" );
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document.write( "6.10x +  6.10*y = 6.10*32   (3)\r\n" );
document.write( "6.10*x + 7.20*y = 211.70    (4)\r\n" );
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document.write( "Now subtract eq(3) from eq(4) (both sides).  The terms \"6.10*x\" will cancel each other,\r\n" );
document.write( "and you will get a single equation for only ONE unknown y   (it is how the Elimination method works)\r\n" );
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document.write( "7.20*y - 6.10*y = 211.70 - 6.10*32,\r\n" );
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document.write( "1.10y = 16.5  ====>  y =  = 15.\r\n" );
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document.write( "Answer.  Blake worked 15 hours for B and 32-15 = 17 hours for A.\r\n" );
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\n" ); document.write( "\n" ); document.write( "On the way, you learned on how the Elimination method works.\r
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