document.write( "Question 1017274: -2x+3y=14 x+2y=7 \n" ); document.write( "

Algebra.Com's Answer #633600 by ikleyn(52879) $\"\"$ $\"About$

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\n" ); document.write( "-2x+3y=14
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document.write( "-2x + 3y = 14,   (1)\r\n" );
document.write( "  x + 2y =  7.   (2)\r\n" );
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document.write( "To solve this system, multiply the equation (2) by 2 and then add to the equation (1). \r\n" );
document.write( "In this way, you eliminate the unknown x and get a single equation for the unknown y:\r\n" );
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document.write( "3y + 4y = 14 + 2*7,   or\r\n" );
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document.write( "7y = 28,\r\n" );
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document.write( "y =  = 4.\r\n" );
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document.write( "You just found y. Now substitute the value y = 4 into equation (2) and get\r\n" );
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document.write( "x + 2*4 = 7.\r\n" );
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document.write( "Hence x = 7 - 8 = -1.\r\n" );
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