document.write( "Question 392083: Nathan's monthly electric bill includes a fixed service charge and an additional charge for the number of kilowatt-hours (kwh) of electricity used. One bill, including a charge for 595 kwh of electricity, is $61.72. Another bill, including a charge for 650 kwh, is $67.11. Find the fixed cahrge and the cost per kilowatt-hour. \n" ); document.write( "
Algebra.Com's Answer #278264 by ankor@dixie-net.com(22740)\"\" \"About 
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Nathan's monthly electric bill includes a fixed service charge and an additional
\n" ); document.write( "charge for the number of kilowatt-hours (kwh) of electricity used.
\n" ); document.write( " One bill, including a charge for 595 kwh of electricity, is $61.72.
\n" ); document.write( " Another bill, including a charge for 650 kwh, is $67.11.
\n" ); document.write( " Find the fixed charge and the cost per kilowatt-hour.
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\n" ); document.write( "Let x = the fixed charge
\n" ); document.write( "Let y = the cost/kwh
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\n" ); document.write( "An equation for each month
\n" ); document.write( "x + 650y = 67.11
\n" ); document.write( "x + 595y = 61.72
\n" ); document.write( "--------------------subtracting eliminate x find y
\n" ); document.write( "55y = 5.39
\n" ); document.write( "y = \"5.39%2F55\"
\n" ); document.write( "y = $.098 per kwh
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\n" ); document.write( "Find the fixed cost (x)
\n" ); document.write( "x + 650(.098) = 67.11
\n" ); document.write( "x + 63.70 = 67.11
\n" ); document.write( "x = 67.11 - 63.70
\n" ); document.write( "x = $3.41
\n" ); document.write( ":
\n" ); document.write( "Check this solution in the 2nd equation
\n" ); document.write( "3.41 + 595(.098) =
\n" ); document.write( "3.41 + 58.31 = 61.72
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