document.write( "Question 199797: I am having trouble with the following problem. I truly need help.\r
\n" ); document.write( "\n" ); document.write( "9x + 24y = 90
\n" ); document.write( "3x + 8y = 30\r
\n" ); document.write( "\n" ); document.write( "These need to be solved using the multiplication/addition method. I have several more problems like this and will use this as an example. I need step by step directions so I can do the other problems. Thank-you so, so much!!!
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Algebra.Com's Answer #150178 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%289x%2B24y=90%2C3x%2B8y=30%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"-3%283x%2B8y%29=-3%2830%29\" Multiply the both sides of the second equation by -3.\r
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\n" ); document.write( "\n" ); document.write( "\"-9x-24y=-90\" 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%289x%2B24y=90%2C-9x-24y=-90%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( "\"%289x%2B24y%29%2B%28-9x-24y%29=%2890%29%2B%28-90%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%289x%2B-9x%29%2B%2824y%2B-24y%29=90%2B-90\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%2B0y=0\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0=0\"Simplify.\r
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\n" ); document.write( "\n" ); document.write( "Since \"0=0\" is always true, this means that there are an infinite number of solutions. \r
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\n" ); document.write( "\n" ); document.write( "So the system is consistent and dependent.\r
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\n" ); document.write( "\n" ); document.write( "If you have any questions, email me at jim_thompson5910@hotmail.com.
\n" ); document.write( "Check out my website if you are interested in tutoring.
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