document.write( "Question 1121799: Determine the x-coordinate of the solution to the system of equations:\r
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Algebra.Com's Answer #737791 by ikleyn(52788)\"\" \"About 
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document.write( "Use the Cramer's rule:\r\n" );
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document.write( "x = \"det_x%2Fdet\",\r\n" );
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document.write( "where det = determinant of the coefficient matrix  det \"%28matrix%282%2C2%2C+1%2C8%2C+-7%2C7%29%29\" = 1*7 - 8*(-7) = 7 + 56 = 63,\r\n" );
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document.write( "det_x = determinant of the matrix obtained by replacing the first column of the coefficient matrix by the right side vector =\r\n" );
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document.write( "      = det \"%28matrix%282%2C2%2C+-29%2C8%2C++-37%2C7%29%29\" = -29*7 - 8*(-37) = 93.\r\n" );
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document.write( "So,  x = \"93%2F63\" = \"31%2F21\".\r\n" );
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document.write( "Answer.  \"31%2F21\".\r\n" );
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\n" ); document.write( "\n" ); document.write( "On Cramer's rule for solving systems of 2 equations in 2 unknowns see the lessons\r
\n" ); document.write( "\n" ); document.write( "    - What is a matrix?,\r
\n" ); document.write( "\n" ); document.write( "    - Determinant of a 2x2-matrix,\r
\n" ); document.write( "\n" ); document.write( "    - HOW TO solve system of linear equations in two unknowns using determinant (Cramer's rule),\r
\n" ); document.write( "\n" ); document.write( "    - Solving systems of linear equations in two unknowns using the Cramer's rule,\r
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\n" ); document.write( "\n" ); document.write( "Also,  you have this free of charge online textbook in ALGEBRA-II in this site\r
\n" ); document.write( "\n" ); document.write( "    - ALGEBRA-II - 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
\n" ); document.write( "     \"2x2-Matrices, determinants, Cramer's rule for systems in two unknowns\" \r
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\n" ); document.write( "\n" ); document.write( "Save the link to this textbook together with its description\r
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\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-II
\n" ); document.write( "https://www.algebra.com/algebra/homework/complex/ALGEBRA-II-YOUR-ONLINE-TEXTBOOK.lesson\r
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\n" ); document.write( "\n" ); document.write( "into your archive and use when it is needed.\r
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