document.write( "Question 1126684: Solve the system of equations by substitution.
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Algebra.Com's Answer #743015 by ikleyn(52878) $\"\"$ $\"About$

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document.write( "6x - y = -5      (1)\r\n" );
document.write( "6x + y = -7      (2)\r\n" );
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document.write( "From eq(2),  express  y = -7 - 6x  and substitute it into equation (1). You will get\r\n" );
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document.write( "6x - (-7-6x) = -5,\r\n" );
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document.write( "6x + 6x + 7 = -5\r\n" );
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document.write( "12x = -5 - 7 = -12  ====>  x =  = -1.\r\n" );
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document.write( "Now substitute this value of x into eq(2) to get\r\n" );
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document.write( "{{6*(-1) + y}}} = -7,    or\r\n" );
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document.write( "-6 + y = -7\r\n" );
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document.write( "y = -7 + 6 = -1.\r\n" );
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document.write( "Answer.  The solution is  x= -1;  y= -1.\r\n" );
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document.write( "    Check the solution on your own by substituting the found values into the original equations.\r\n" );
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document.write( "    Do it on your own (I just did it mentally).\r\n" );
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\n" ); document.write( "\n" ); document.write( "See the lesson\r
\n" ); document.write( "\n" ); document.write( " - Solution of the linear system of two equations in two unknowns by the Substitution method \r
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