document.write( "Question 992502: Solve the system:
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Algebra.Com's Answer #612154 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "- x - y -2z =   9,     (1)\r\n" );
document.write( "-2x -2y - z =   1,     (2)\r\n" );
document.write( "- x - y + z = -10.     (3)\r\n" );
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document.write( "Distract equation  (1)  from  equatin (3).  You will get\r\n" );
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document.write( "3z = -10 -9 = -19.     (4)\r\n" );
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document.write( "Now multiply equation  (3)  by  2  and then distract the equation  (2).  You will get\r\n" );
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document.write( "3z = 2*(-10) - 1 = -20 -1 = -21.     (5)\r\n" );
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document.write( "You have two equations for  z,  (4)  and  (5),  and they are inconsistent.\r\n" );
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document.write( "Hence,  the original system is inconsistent.\r\n" );
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document.write( "Answer.  This system has no solutions.\r\n" );
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document.write( "By the way,  the determinant of the system is equal to zero.\r\n" );
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