document.write( "Question 181961: Find the values of x and y that solve the following systems of equations.\r
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Algebra.Com's Answer #136579 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%286x%2B7y=-5%2C4x%2B3y=-15%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"2%286x%2B7y%29=2%28-5%29\" Multiply the both sides of the first equation by 2.\r
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\n" ); document.write( "\n" ); document.write( "\"12x%2B14y=-10\" Distribute and multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-3%284x%2B3y%29=-3%28-15%29\" Multiply the both sides of the second equation by -3.\r
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\n" ); document.write( "\n" ); document.write( "\"-12x-9y=45\" 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%2B14y=-10%2C-12x-9y=45%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%2B14y%29%2B%28-12x-9y%29=%28-10%29%2B%2845%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%2812x%2B-12x%29%2B%2814y%2B-9y%29=-10%2B45\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%2B5y=35\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"5y=35\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%2835%29%2F%285%29\" Divide both sides by \"5\" 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( "\"12x%2B14y=-10\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"12x%2B14%287%29=-10\" Plug in \"y=7\".\r
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\n" ); document.write( "\n" ); document.write( "\"12x%2B98=-10\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"12x=-10-98\" Subtract \"98\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"12x=-108\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-108%29%2F%2812%29\" Divide both sides by \"12\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=-9\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \"x=-9\" and \"y=7\".\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 \"6x%2B7y=-5\" (red) and \"4x%2B3y=-15\" (green) \r
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