document.write( "Question 999141: solve using addition method\r
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Algebra.Com's Answer #616848 by ikleyn(52797) $\"\"$ $\"About$

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document.write( "3x + 7y =  16   (1)\r\n" );
document.write( "2x - 3y = -11   (2)\r\n" );
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document.write( "Multiply (1) by 3 (both sides) and (2) by 7 (both sides). \r\n" );
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document.write( "9x + 21y =  48   (1')\r\n" );
document.write( "14x -21y = -77   (2')\r\n" );
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document.write( "Now add (1') and (2'). In this way you will exclude y and will obtain a single equation for x:\r\n" );
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document.write( "9x + 14x = 48 - 77, or\r\n" );
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document.write( "23x = -29.\r\n" );
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document.write( "Hence, x = .\r\n" );
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document.write( "Now substitute this value of x into the equation (1) and solve it for y.\r\n" );
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document.write( "The numbers are really not very impressive, but they are your numbers, not my.\r\n" );
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