document.write( "Question 198012: I have gotten thru 4 of the 8 questions on my worksheet and am stuck with this one. the direction say to \"solve each system by elimination\"\r
\n" ); document.write( "\n" ); document.write( "12x - 7y = -10
\n" ); document.write( "-4x + 3y = 10\r
\n" ); document.write( "\n" ); document.write( "I can't seem to get either side to cancel out.
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Algebra.Com's Answer #148492 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "Start with the given system of equations:\r
\n" ); document.write( "\n" ); document.write( "\"system%2812x-7y=-10%2C-4x%2B3y=10%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"3%28-4x%2B3y%29=3%2810%29\" Multiply the both sides of the second equation by 3.\r
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\n" ); document.write( "\n" ); document.write( "\"-12x%2B9y=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%2812x-7y=-10%2C-12x%2B9y=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( "\"%2812x-7y%29%2B%28-12x%2B9y%29=%28-10%29%2B%2830%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%2812x%2B-12x%29%2B%28-7y%2B9y%29=-10%2B30\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%2B2y=20\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"2y=20\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%2820%29%2F%282%29\" Divide both sides by \"2\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=10\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"12x-7y=-10\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"12x-7%2810%29=-10\" Plug in \"y=10\".\r
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\n" ); document.write( "\n" ); document.write( "\"12x-70=-10\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"12x=-10%2B70\" Add \"70\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"12x=60\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2860%29%2F%2812%29\" Divide both sides by \"12\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=5\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=5\" and \"y=10\".\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 \"12x-7y=-10\" (red) and \"-4x%2B3y=10\" (green)
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