document.write( "Question 243643: find the coordinates of -x+3y=12, and 4x+3y=12 \n" ); document.write( "
Algebra.Com's Answer #178463 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%28-x%2B3y=12%2C4x%2B3y=12%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"4%28-x%2B3y%29=4%2812%29\" Multiply the both sides of the first equation by 4.\r
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\n" ); document.write( "\n" ); document.write( "\"-4x%2B12y=48\" 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%28-4x%2B12y=48%2C4x%2B3y=12%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( "\"%28-4x%2B12y%29%2B%284x%2B3y%29=%2848%29%2B%2812%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28-4x%2B4x%29%2B%2812y%2B3y%29=48%2B12\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%2B15y=60\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"15y=60\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%2860%29%2F%2815%29\" Divide both sides by \"15\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=4\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"-4x%2B12y=48\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-4x%2B12%284%29=48\" Plug in \"y=4\".\r
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\n" ); document.write( "\n" ); document.write( "\"-4x%2B48=48\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-4x=48-48\" Subtract \"48\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-4x=0\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%280%29%2F%28-4%29\" Divide both sides by \"-4\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=0\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=0\" and \"y=4\".\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 \"-x%2B3y=12\" (red) and \"4x%2B3y=12\" (green)
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