document.write( "Question 146700: X=2y-7
\n" ); document.write( "3X +2y=-5
\n" ); document.write( "use addition method
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Algebra.Com's Answer #107131 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Start with the given system of equations:\r
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\n" ); document.write( "\n" ); document.write( "\"x=2y-7\" Start with the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"x-2y=-7\" Subtract \"2y\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "So we have the new system of equations:\r
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\n" ); document.write( "\n" ); document.write( "\"system%28x-2y=-7%2C3x%2B2y=-5%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-2y%29%2B%283x%2B2y%29=%28-7%29%2B%28-5%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%281x%2B3x%29%2B%28-2y%2B2y%29=-7%2B-5\" 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=%28-12%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-2y=-7\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-3-2y=-7\" Plug in \"x=-3\".\r
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\n" ); document.write( "\n" ); document.write( "\"-3-2y=-7\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-2y=-7%2B3\" Add \"3\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-2y=-4\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-4%29%2F%28-2%29\" Divide both sides by \"-2\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=2\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \"x=-3\" and \"y=2\".\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 two equations are 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-2y=-7\" (red) and \"3x%2B2y=-5\" (green) \r
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