document.write( "Question 157504: Solve by the addition method?\r
\n" ); document.write( "\n" ); document.write( "6x - y = 49
\n" ); document.write( "x + 6y = 39\r
\n" ); document.write( "\n" ); document.write( "What is the solution of the system?
\n" ); document.write( "(Simplify you answer. Type an order pair?)
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Algebra.Com's Answer #116067 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%286x-y=49%2Cx%2B6y=39%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"-6%28x%2B6y%29=-6%2839%29\" Multiply the both sides of the second equation by -6.\r
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\n" ); document.write( "\n" ); document.write( "\"-6x-36y=-234\" 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%286x-1y=49%2C-6x-36y=-234%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( "\"%286x-1y%29%2B%28-6x-36y%29=%2849%29%2B%28-234%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%286x%2B-6x%29%2B%28-1y%2B-36y%29=49%2B-234\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%2B-37y=-185\" Combine like terms. Notice how the x terms cancel out.\r
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\n" ); document.write( "\n" ); document.write( "\"-37y=-185\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-185%29%2F%28-37%29\" Divide both sides by \"-37\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=5\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"6x-1y=49\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"6x-1%285%29=49\" Plug in \"y=5\".\r
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\n" ); document.write( "\n" ); document.write( "\"6x-5=49\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"6x=49%2B5\" Add \"5\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"6x=54\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2854%29%2F%286%29\" Divide both sides by \"6\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=9\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \"x=9\" and \"y=5\".\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 \"6x-y=49\" (red) and \"x%2B6y=39\" (green) \r
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\n" ); document.write( "\n" ); document.write( "Questions? Email me at jim_thompson5910@hotmail.com
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