document.write( "Question 1197987: the sum of a and b is 28 the difference between a and 2b is 10 \n" ); document.write( "
Algebra.Com's Answer #831472 by ikleyn(52790)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "    the sum of a and b is 28 and the difference a - 2b is 10.\r\n" );
document.write( "    Find \"a\" and \"b\".\r\n" );
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document.write( "    a +  b = 28,    (1)\r\n" );
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document.write( "    a - 2b = 10.    (2)\r\n" );
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document.write( "From equation (1), subtract equation (2).  The terms with \"a\" will cancel each other, and you will get\r\n" );
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document.write( "    b - (-2b) = 28 - 10\r\n" );
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document.write( "      3b      =    18\r\n" );
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document.write( "       b      =    18/3 = 6.\r\n" );
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document.write( "Then from equation (1),  a = 28 - b = 28 - 6 = 22.\r\n" );
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document.write( "ANSWER.  a = 22;  b = 6.\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
\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( "    - Useful tricks when solving systems of 2 equations in 2 unknowns by the Substitution method \r
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\n" ); document.write( "\n" ); document.write( "They give you the general theory and a lot of examples which you can consider as your TEMPLATES.\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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