document.write( "Question 1126685: Solve the system of equations by elimination.
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Algebra.Com's Answer #743014 by ikleyn(52787) $\"\"$ $\"About$

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document.write( "2x +  y = 13,     (1)\r\n" );
document.write( "4x + 5y = 11.     (2)\r\n" );
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document.write( "Multiply eq(1) by the factor 2 (both sides). Keep the equation (2) as is.  You will get an equivalent system\r\n" );
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document.write( "4x + 2y = 26      (1')\r\n" );
document.write( "4x + 5y = 11      (2')\r\n" );
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document.write( "Now subtract  eq(1') from eq(2').  The terms \"4x\" will cancel each other,    (<<<---=== it is how the Elimination method works)\r\n" );
document.write( "and you will get a single equation for the unknown \"y\"\r\n" );
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document.write( "5y - 2y = 11 - 26,   or\r\n" );
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document.write( "3y = -15,\r\n" );
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document.write( "which implies  y = -15/3 = -5.\r\n" );
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document.write( "Now from equation (1),  2*x - 5 = 13;  hence,  2x = 13 + 5 = 18   and  x = 18/2 = 9.\r\n" );
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document.write( "    Check the solution on your own by substituting the found values into the original equation.\r\n" );
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document.write( "    Do it on your own (I just did it mentally).\r\n" );
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document.write( "Answer  x= 9;  y= -5.\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 Elimination method \r
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