document.write( "Question 178816: determine the best method to solve each system of equations. then solve the system.
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\n" ); document.write( "2x+5y=13
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Algebra.Com's Answer #133784 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Elimination is the easiest way to solve this system.\r
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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-5y=7%2C2x%2B5y=13%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( "\"%283x-5y%29%2B%282x%2B5y%29=%287%29%2B%2813%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%283x%2B2x%29%2B%28-5y%2B5y%29=7%2B13\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"5x%2B0y=20\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"5x=20\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2820%29%2F%285%29\" Divide both sides by \"5\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=4\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"3x-5y=7\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"3%284%29-5y=7\" Plug in \"x=4\".\r
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\n" ); document.write( "\n" ); document.write( "\"12-5y=7\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-5y=7-12\" Subtract \"12\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-5y=-5\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-5%29%2F%28-5%29\" Divide both sides by \"-5\" 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=4\" 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-5y=7\" (red) and \"2x%2B5y=13\" (green)
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