document.write( "Question 218289: I need to know if my answer is correct for the following: If it isn't, I need to know why. thanks
\n" ); document.write( "Solve the system of equations
\n" ); document.write( "x+2y=1
\n" ); document.write( "3x-2y=11
\n" ); document.write( "My answer is (3,-1)
\n" ); document.write( "Thank you very much!
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Algebra.Com's Answer #164447 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%28x%2B2y=1%2C3x-2y=11%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( "\"%28x%2B2y%29%2B%283x-2y%29=%281%29%2B%2811%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%281x%2B3x%29%2B%282y%2B-2y%29=1%2B11\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"4x%2B0y=12\" Combine like terms. Notice how the y terms cancel out.\r
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\n" ); document.write( "\n" ); document.write( "\"4x=12\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2812%29%2F%284%29\" Divide both sides by \"4\" 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( "\"x%2B2y=1\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"3%2B2y=1\" Plug in \"x=3\".\r
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\n" ); document.write( "\n" ); document.write( "\"3%2B2y=1\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"2y=1-3\" Subtract \"3\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"2y=-2\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-2%29%2F%282%29\" Divide both sides by \"2\" 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( "So our answer is \"x=3\" and \"y=-1\".\r
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\n" ); document.write( "\n" ); document.write( "Which form the ordered pair . Good job. As a check, simply plug in \"x=3\" and \"y=-1\" and you should get two identities.\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=1\" (red) and \"3x-2y=11\" (green) \r
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