document.write( "Question 189588: x+2y=10,
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Algebra.Com's Answer #142272 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Start with the given system of equations:\r
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\n" ); document.write( "\n" ); document.write( "\"-3%28x%2B2y%29=-3%2810%29\" Multiply the both sides of the first equation by -3.\r
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\n" ); document.write( "\n" ); document.write( "\"-3x-6y=-30\" 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%28-3x-6y=-30%2C3x%2B4y=8%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( "\"%28-3x-6y%29%2B%283x%2B4y%29=%28-30%29%2B%288%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28-3x%2B3x%29%2B%28-6y%2B4y%29=-30%2B8\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%2B-2y=-22\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"-2y=-22\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-22%29%2F%28-2%29\" Divide both sides by \"-2\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=11\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"-3x-6y=-30\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-3x-6%2811%29=-30\" Plug in \"y=11\".\r
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\n" ); document.write( "\n" ); document.write( "\"-3x-66=-30\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-3x=-30%2B66\" Add \"66\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-3x=36\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2836%29%2F%28-3%29\" Divide both sides by \"-3\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=-12\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=-12\" and \"y=11\".\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.\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph the equations, we see that they intersect at . So this visually verifies our answer.\r
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\n" ); document.write( "\n" ); document.write( " Graph of \"x%2B2y=10\" (red) and \"3x%2B4y=8\" (green)
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