document.write( "Question 1196230: During one month, a homeowner used 200 units of electricity and 110 units of gas for a total cost of $87.80. The next month, 240 units of electricity and 200 units of gas were used for a total cost of $117.60. Find the cost per unit of gas. \n" ); document.write( "
Algebra.Com's Answer #828980 by ikleyn(52803)\"\" \"About 
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\n" ); document.write( "During one month, a homeowner used 200 units of electricity and 110 units of gas for a total cost of $87.80.
\n" ); document.write( "The next month, 240 units of electricity and 200 units of gas were used for a total cost of $117.60.
\n" ); document.write( "Find the cost per unit of gas.
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document.write( "Write the system of two equations\r\n" );
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document.write( "    200e + 110g = 87.80\r\n" );
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document.write( "    240e + 200g = 117.60\r\n" );
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document.write( "where \"e\" is the price for the unit of electricity and \"g\" is the price for the unit of gas.\r\n" );
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document.write( "Solve using determinants\r\n" );
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document.write( "    g = \"%28200%2A117.60+-+240%2A87.80%29%2F%28200%2A200+-+240%2A110%29\" = 0.18.\r\n" );
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document.write( "ANSWER. The cost per unit of gas is 0.18.\r\n" );
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\n" ); document.write( "\n" ); document.write( "On the  Determinants' method for solving systems of two linear equations in two unknowns see the lesson \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( "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 lesson is 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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