document.write( "Question 255417: 7x+2y=24
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Algebra.Com's Answer #187693 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%287x%2B2y=24%2C8x%2B2y=30%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"-1%288x%2B2y%29=-1%2830%29\" Multiply the both sides of the second equation by -1.\r
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\n" ); document.write( "\n" ); document.write( "\"-8x-2y=-30\" 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%287x%2B2y=24%2C-8x-2y=-30%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( "\"%287x%2B2y%29%2B%28-8x-2y%29=%2824%29%2B%28-30%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%287x%2B-8x%29%2B%282y%2B-2y%29=24%2B-30\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"-x%2B0y=-6\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"-x=-6\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-6%29%2F%28-1%29\" Divide both sides by \"-1\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=6\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"7x%2B2y=24\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"7%286%29%2B2y=24\" Plug in \"x=6\".\r
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\n" ); document.write( "\n" ); document.write( "\"42%2B2y=24\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"2y=24-42\" Subtract \"42\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"2y=-18\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-18%29%2F%282%29\" Divide both sides by \"2\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=-9\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=6\" and \"y=-9\".\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 \"7x%2B2y=24\" (red) and \"8x%2B2y=30\" (green)
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