document.write( "Question 374762: Please solve each system\r
\n" ); document.write( "\n" ); document.write( "-5x + 2y = 9
\n" ); document.write( "-3x + 8y = -15
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Algebra.Com's Answer #266508 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%28-5x%2B2y=9%2C-3x%2B8y=-15%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"-4%28-5x%2B2y%29=-4%289%29\" Multiply the both sides of the first equation by -4.\r
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\n" ); document.write( "\n" ); document.write( "\"20x-8y=-36\" 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%2820x-8y=-36%2C-3x%2B8y=-15%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( "\"%2820x-8y%29%2B%28-3x%2B8y%29=%28-36%29%2B%28-15%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%2820x%2B-3x%29%2B%28-8y%2B8y%29=-36%2B-15\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"17x%2B0y=-51\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"17x=-51\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-51%29%2F%2817%29\" Divide both sides by \"17\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=-3\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"20x-8y=-36\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"20%28-3%29-8y=-36\" Plug in \"x=-3\".\r
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\n" ); document.write( "\n" ); document.write( "\"-60-8y=-36\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-8y=-36%2B60\" Add \"60\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-8y=24\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%2824%29%2F%28-8%29\" Divide both sides by \"-8\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=-3\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=-3\" and \"y=-3\".\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 \"-5x%2B2y=9\" (red) and \"-3x%2B8y=-15\" (green) \r
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\n" ); document.write( "\n" ); document.write( "If you need more help, email me at jim_thompson5910@hotmail.com\r
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\n" ); document.write( "\n" ); document.write( "Also, feel free to check out my tutoring website\r
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\n" ); document.write( "\n" ); document.write( "Jim
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