document.write( "Question 376347: the problem that I am solving through substitution is 9x + 2y = -51(equation 1) and -9x + y =69(equation 2), I substituted with a fraction in place of x and also got a fraction for y and it was wrong, how do I properly calculate fraction answers at this point? \n" ); document.write( "
Algebra.Com's Answer #267767 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%289x%2B2y=-51%2C-9x%2By=69%29\"\r
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\n" ); document.write( "\n" ); document.write( "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( "\"%289x%2B2y%29%2B%28-9x%2By%29=%28-51%29%2B%2869%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%289x%2B-9x%29%2B%282y%2B1y%29=-51%2B69\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%2B3y=18\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"3y=18\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%2818%29%2F%283%29\" Divide both sides by \"3\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=6\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"9x%2B2y=-51\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"9x%2B2%286%29=-51\" Plug in \"y=6\".\r
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\n" ); document.write( "\n" ); document.write( "\"9x%2B12=-51\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"9x=-51-12\" Subtract \"12\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"9x=-63\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-63%29%2F%289%29\" Divide both sides by \"9\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=-7\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=-7\" and \"y=6\".\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 \"9x%2B2y=-51\" (red) and \"-9x%2By=69\" (green) \r
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\n" ); document.write( "\n" ); document.write( "If you need more help, email me at jim_thompson5910@hotmail.com\r
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\n" ); document.write( "\n" ); document.write( "Also, feel free to check out my tutoring website\r
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\n" ); document.write( "\n" ); document.write( "Jim
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