document.write( "Question 183033: HELP, I think the answer is x=7 and y=7 but how do you set this up. Use elimination to solve each system of equations. 4X-2Y=14 Y=X \n" ); document.write( "
Algebra.Com's Answer #137407 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\"y=x\" Start with the second equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-x%2By=0\" Subtract \"x\" from both sides (the goal is to get all the variable terms to the left side).\r
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\n" ); document.write( "\n" ); document.write( "So we have the system of equations:\r
\n" ); document.write( "\n" ); document.write( "\"system%284x-2y=14%2C-x%2By=0%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"2%28-x%2By%29=2%280%29\" Multiply the both sides of the second equation by 2.\r
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\n" ); document.write( "\n" ); document.write( "\"-2x%2B2y=0\" 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%284x-2y=14%2C-2x%2B2y=0%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( "\"%284x-2y%29%2B%28-2x%2B2y%29=%2814%29%2B%280%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%284x%2B-2x%29%2B%28-2y%2B2y%29=14%2B0\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"2x%2B0y=14\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"2x=14\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2814%29%2F%282%29\" Divide both sides by \"2\" 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( "\"4x-2y=14\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"4%287%29-2y=14\" Plug in \"x=7\".\r
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\n" ); document.write( "\n" ); document.write( "\"28-2y=14\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-2y=14-28\" Subtract \"28\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-2y=-14\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-14%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=7\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \"x=7\" and \"y=7\" (so you are correct).\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 \"4x-2y=14\" (red) and \"y=x\" (green) \r
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