document.write( "Question 1196577: 3x + 5y =54
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Algebra.Com's Answer #829479 by ikleyn(52786)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "You want to solve a system of two equations in two unknowns\r\n" );
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document.write( "    3x + 5y = 54      (1)\r\n" );
document.write( "    6x + 4y = 72      (2)\r\n" );
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document.write( "Divide second equation by 2 (both sides).  Keep equation (1) as is.\r\n" );
document.write( "You will get\r\n" );
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document.write( "    3x + 5y = 54      (1)\r\n" );
document.write( "    3x + 2y = 36      (2')\r\n" );
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document.write( "Now subtract equarion (2') from equation (1).\r\n" );
document.write( "The terms with \"x\" will cancel each other, since they have equal coefficients.\r\n" );
document.write( "You will get\r\n" );
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document.write( "         5y - 2y = 54 - 36\r\n" );
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document.write( "            3y   =    18\r\n" );
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document.write( "             y   =    18/3 = 6.\r\n" );
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document.write( "To find x, substitute y= 6 into equation (1). You will get  \r\n" );
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document.write( "    3x + 4*6 = 54  --->  3x = 54 - 30 = 24  --->  x = 24/3 = 8.\r\n" );
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document.write( "ANSWER.  x= 8,  y= 6.\r\n" );
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document.write( "CHECK.  To check, substitute the found values into given equations; \r\n" );
document.write( "        calculate left sides and compare with right sides.\r\n" );
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\n" ); document.write( "\n" ); document.write( "It looks like you need to learn  (to get familiar with)  the general theory/technique on solving systems of two equations in two unknown.\r
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\n" ); document.write( "\n" ); document.write( "In this site I developed such lessons for beginner students.  These lessons are\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
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\n" ); document.write( "\n" ); document.write( "Consider these lessons as your textbook,  your handbook,  your guide and your  (free of charge)  home teacher.\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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\n" ); document.write( "\n" ); document.write( "Save the link to this online textbook together with its description\r
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\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-I
\n" ); document.write( "https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson\r
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\n" ); document.write( "\n" ); document.write( "to your archive and use it when it is needed.\r
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