document.write( "Question 1189285: ​
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\n" ); document.write( "21x+7y=42
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\n" ); document.write( "what would x and y be? I am not sure how to solve these problems if the equations don't equal y. \n" ); document.write( "
Algebra.Com's Answer #820604 by ikleyn(52788)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "what would x and y be? I am not sure how to solve these problems if the equations don't equal y.
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document.write( "Your starting equations are\r\n" );
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document.write( "    21x + 7y = 42      (1)\r\n" );
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document.write( "    −5x + 5y = 10      (2)\r\n" );
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document.write( "In the first equation, divide both sides by 7.\r\n" );
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document.write( "In the second equation, divide both sides by 5. You will get an EQUIVALENT system of equations\r\n" );
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document.write( "    3x + y = 6        (3)\r\n" );
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document.write( "    -x + y = 2.       (4)\r\n" );
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document.write( "From equation (3), subtract equation (4). You will get then, after canceling the terms with \"y\"\r\n" );
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document.write( "    3x - (-x) = 6 - 2\r\n" );
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document.write( "       4x     =   4\r\n" );
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document.write( "        x     =   4/4 = 1.\r\n" );
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document.write( "Next, substitute x= 1 into equation (4).  You will get\r\n" );
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document.write( "    -1 + y = 2,\r\n" );
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document.write( "or       y = 2 + 1 = 3.\r\n" );
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document.write( "ANSWER.  The solution to the given system opf equations is  x= 1,  y= 3.\r\n" );
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document.write( "CHECK.   Check it ON YOUR OWN, that the found values x= 1, y= 3 satisfy the given equations (1) and (2).\r\n" );
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\n" ); document.write( "\n" ); document.write( "As I see from your post, the level of your knowledge is about zero on this subject.\r
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\n" ); document.write( "\n" ); document.write( "On solving systems of linear equations, see the lessons\r
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