document.write( "Question 166281: -x-5y=-1
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Algebra.Com's Answer #122544 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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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%28-x-5y=-1%2C2x%2B3y=-5%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"2%28-x-5y%29=2%28-1%29\" Multiply the both sides of the first equation by 2.\r
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\n" ); document.write( "\n" ); document.write( "\"-2x-10y=-2\" 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-10y=-2%2C2x%2B3y=-5%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-10y%29%2B%282x%2B3y%29=%28-2%29%2B%28-5%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28-2x%2B2x%29%2B%28-10y%2B3y%29=-2%2B-5\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%2B-7y=-7\" Combine like terms. Notice how the x terms cancel out.\r
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\n" ); document.write( "\n" ); document.write( "\"-7y=-7\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-7%29%2F%28-7%29\" Divide both sides by \"-7\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=1\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"-2x-10y=-2\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-2x-10%281%29=-2\" Plug in \"y=1\".\r
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\n" ); document.write( "\n" ); document.write( "\"-2x-10=-2\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-2x=-2%2B10\" Add \"10\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-2x=8\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%288%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=-4\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \"x=-4\" and \"y=1\".\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-5y=-1\" (red) and \"2x%2B3y=-5\" (green) \r
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