document.write( "Question 207149: Solve the system by the addition method. Determine whether the equations are independent, dependent, or inconsistent.
\n" ); document.write( "3x - 2y = -7
\n" ); document.write( "x – 5y = 2
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Algebra.Com's Answer #156596 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%283x-2y=-7%2Cx-5y=2%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"-3%28x-5y%29=-3%282%29\" Multiply the both sides of the second equation by -3.\r
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\n" ); document.write( "\n" ); document.write( "\"-3x%2B15y=-6\" 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%283x-2y=-7%2C-3x%2B15y=-6%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( "\"%283x-2y%29%2B%28-3x%2B15y%29=%28-7%29%2B%28-6%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%283x%2B-3x%29%2B%28-2y%2B15y%29=-7%2B-6\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%2B13y=-13\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"13y=-13\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-13%29%2F%2813%29\" Divide both sides by \"13\" 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( "\"3x-2y=-7\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"3x-2%28-1%29=-7\" Plug in \"y=-1\".\r
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\n" ); document.write( "\n" ); document.write( "\"3x%2B2=-7\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"3x=-7-2\" Subtract \"2\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"3x=-9\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-9%29%2F%283%29\" Divide both sides by \"3\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=-3\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=-3\" 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 \"3x-2y=-7\" (red) and \"x-5y=2\" (green) \r
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