document.write( "Question 1149916: Solving Systems Using Elimination. Your math test has 38 questions and is worth 200 points. The test consist of multiple choice questions worth 4 points each and open ended questions worth 20 points each. How many of each type of question are there? \r
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Algebra.Com's Answer #771251 by ikleyn(52790)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Your start is fine.\r\n" );
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document.write( "The next steps are\r\n" );
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document.write( "     x +  y =   38    (1)\r\n" );
document.write( "    4x + 20y = 200    (2)\r\n" );
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document.write( "To solve by Elimination, multiply equation (1) by 4 (both sides). Keep equation (2) as is.\r\n" );
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document.write( "    4x + 4y =  4*38   (1')\r\n" );
document.write( "    4x + 20y = 200    (2')\r\n" );
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document.write( "Now subtract equation (1') from equation (2').  The terms \" 4x \" will kill each other, and you will get single equation \r\n" );
document.write( "for variable \"y\" only (!)\r\n" );
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document.write( "         20y - 4y = 200 - 4*38 \r\n" );
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document.write( "         16y      = 48\r\n" );
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document.write( "           y      = 48/16 = 3.\r\n" );
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document.write( "It how the Elimination method works.\r\n" );
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document.write( "Finally, substitute the value y= 3 into equation (1) to get \"x\".\r\n" );
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document.write( "          x + 3 = 38\r\n" );
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document.write( "          x     = 38-3 = 35.\r\n" );
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document.write( "ANSWER.  x= 35;  y= 3.\r\n" );
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\n" ); document.write( "\n" ); document.write( "In this site, there is a large group of lessons on solving 2x2-system of linear equations\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
\n" ); document.write( "\n" ); document.write( "    - Solving word problems using linear systems of two equations in two unknowns \r
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\n" ); document.write( "\n" ); document.write( "    - Oranges and grapefruits \r
\n" ); document.write( "\n" ); document.write( "    - Using systems of equations to solve problems on tickets \r
\n" ); document.write( "\n" ); document.write( "    - Three methods for solving standard (typical) problems on tickets\r
\n" ); document.write( "\n" ); document.write( "    - Using systems of equations to solve problems on shares \r
\n" ); document.write( "\n" ); document.write( "    - Using systems of equations to solve problems on investment\r
\n" ); document.write( "\n" ); document.write( "    - Two mechanics work on a car \r
\n" ); document.write( "\n" ); document.write( "    - The Robinson family and the Sanders family each used their sprinklers last summer\r
\n" ); document.write( "\n" ); document.write( "    - Roses and vilolets \r
\n" ); document.write( "\n" ); document.write( "    - Counting calories and grams of fat in combined food\r
\n" ); document.write( "\n" ); document.write( "    - A theater group made appearances in two cities\r
\n" ); document.write( "\n" ); document.write( "    - HOW TO algebreze and solve this problem on 2 equations in 2 unknowns \r
\n" ); document.write( "\n" ); document.write( "    - One unusual problem to solve using system of two equations \r
\n" ); document.write( "\n" ); document.write( "    - Solving mentally word problems on two equations in two unknowns \r
\n" ); document.write( "\n" ); document.write( "    - Solving systems of non-linear equations by reducing to linear ones \r
\n" ); document.write( "\n" ); document.write( "    - System of equations helps to solve a problem for the Thanksgiving day\r
\n" ); document.write( "\n" ); document.write( "    - Using system of two equations to solve the problem for the day of April, 1 \r
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\n" ); document.write( "\n" ); document.write( "    - OVERVIEW of lessons on solving systems of two linear equations in two unknowns\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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