document.write( "Question 1085620: solve simultaneous equations algebraically
\n" ); document.write( "2y+x=9
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Algebra.Com's Answer #699712 by ikleyn(52781) $\"\"$ $\"About$

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\n" ); document.write( "solve simultaneous equations algebraically
\n" ); document.write( "2y+x=9
\n" ); document.write( "3y-5x=20
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document.write( "2y +  x =  9,    (1)\r\n" );
document.write( "3y - 5x = 20.    (2)\r\n" );
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document.write( "Multiply equation (1) by 5 (both sides). You will get an equivalent system\r\n" );
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document.write( "10y + 5x = 45,   (3)\r\n" );
document.write( " 3y - 5x = 20.   (4)\r\n" );
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document.write( "Add the equations (3) and (4). The terms with \"x\" will cancel, and you will get\r\n" );
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document.write( "13y = 45 + 20 = 65,  ---->  y =  = 5.\r\n" );
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document.write( "Then from the equation (1) x = 9 - 2y = 9 - 2*5 = 9 - 10 = -1.\r\n" );
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document.write( "Answer.  x= -1, y=5.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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\n" ); document.write( "\n" ); document.write( "The method I applied is called \"the Elimination method\".\r
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\n" ); document.write( "\n" ); document.write( "On solving systems of two linear equations in two unknowns see the lessons \r
\n" ); document.write( "\n" ); document.write( "    - Solution of the linear system of two equations in two unknowns by the Substitution method \r
\n" ); document.write( "\n" ); document.write( "    - Solution of the linear system of two equations in two unknowns by the Elimination method \r
\n" ); document.write( "\n" ); document.write( "    - Solution of the linear system of two equations in two unknowns using determinant \r
\n" ); document.write( "\n" ); document.write( "    - Geometric interpretation of the linear system of two equations in two unknowns \r
\n" ); document.write( "\n" ); document.write( "in this site.\r
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\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook in ALGEBRA-I in this site\r
\n" ); document.write( "\n" ); document.write( "    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this online textbook under the topic \"Systems of two linear equations in two unknowns\".\r
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