document.write( "Question 197997: A first number plus twice a second number is 5. Twice the first number plus the second totals 4. Find the numbers. \n" ); document.write( "
Algebra.Com's Answer #148476 by jim_thompson5910(35256)\"\" \"About 
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\"A first number plus twice a second number is 5. Twice the first number plus the second totals 4\" translates to the system: \"system%28x%2B2y=5%2C2x%2By=4%29\"\r
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\n" ); document.write( "\n" ); document.write( "Start with the given system of equations:\r
\n" ); document.write( "\n" ); document.write( "\"system%28x%2B2y=5%2C2x%2By=4%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"-2%28x%2B2y%29=-2%285%29\" Multiply the both sides of the first equation by -2.\r
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\n" ); document.write( "\n" ); document.write( "\"-2x-4y=-10\" 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%28-2x-4y=-10%2C2x%2By=4%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( "\"%28-2x-4y%29%2B%282x%2By%29=%28-10%29%2B%284%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28-2x%2B2x%29%2B%28-4y%2B1y%29=-10%2B4\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%2B-3y=-6\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"-3y=-6\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-6%29%2F%28-3%29\" Divide both sides by \"-3\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=2\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"-2x-4y=-10\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-2x-4%282%29=-10\" Plug in \"y=2\".\r
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\n" ); document.write( "\n" ); document.write( "\"-2x-8=-10\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-2x=-10%2B8\" Add \"8\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-2x=-2\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-2%29%2F%28-2%29\" Divide both sides by \"-2\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=1\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=1\" and \"y=2\".\r
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\n" ); document.write( "\n" ); document.write( "which means that the first number is 1 and the second number is 2
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