document.write( "Question 192048: Solve by elimination\r
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\n" ); document.write( "\n" ); document.write( "0.05x+0.25y=66
\n" ); document.write( "0.15+0.05y=72\r
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Algebra.Com's Answer #144106 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"0.05x%2B0.25y=66\" Start with the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"100%280.05x%2B0.25y%29=100%2866%29\" Multiply both sides by 100 to clear out the decimals.\r
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\n" ); document.write( "\n" ); document.write( "\"5x%2B25y=6600\" Distribute and multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"0.15x%2B0.05y=72\" Move onto the second equation.\r
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\n" ); document.write( "\n" ); document.write( "\"100%280.15x%2B0.05y%29=100%2872%29\" Multiply both sides by 100 to clear out the decimals.\r
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\n" ); document.write( "\n" ); document.write( "\"15x%2B5y=7200\" Distribute and multiply.\r
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\n" ); document.write( "\n" ); document.write( "So we have the system of equations:\r
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\n" ); document.write( "\n" ); document.write( "\"system%285x%2B25y=6600%2C15x%2B5y=7200%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"-5%2815x%2B5y%29=-5%287200%29\" Multiply the both sides of the second equation by -5.\r
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\n" ); document.write( "\n" ); document.write( "\"-75x-25y=-36000\" Distribute and multiply.\r
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\n" ); document.write( "\n" ); document.write( "So we have the new system of equations:\r
\n" ); document.write( "\n" ); document.write( "\"system%285x%2B25y=6600%2C-75x-25y=-36000%29\"\r
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\n" ); document.write( "\n" ); document.write( "Now add the equations together. You can do this by simply adding the two left sides and the two right sides separately like this:\r
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\n" ); document.write( "\n" ); document.write( "\"%285x%2B25y%29%2B%28-75x-25y%29=%286600%29%2B%28-36000%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%285x%2B-75x%29%2B%2825y%2B-25y%29=6600%2B-36000\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"-70x%2B0y=-29400\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"-70x=-29400\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-29400%29%2F%28-70%29\" Divide both sides by \"-70\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=420\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"5x%2B25y=6600\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"5%28420%29%2B25y=6600\" Plug in \"x=420\".\r
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\n" ); document.write( "\n" ); document.write( "\"2100%2B25y=6600\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"25y=6600-2100\" Subtract \"2100\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"25y=4500\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%284500%29%2F%2825%29\" Divide both sides by \"25\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=180\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=420\" and \"y=180\".\r
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\n" ); document.write( "\n" ); document.write( "Which form the ordered pair .\r
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\n" ); document.write( "\n" ); document.write( "This means that the system is consistent and independent.
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