document.write( "Question 175480: i need help doing this problem:\r
\n" ); document.write( "\n" ); document.write( "-3a + b = 4 \r
\n" ); document.write( "\n" ); document.write( "-9a + 5b = -1\r
\n" ); document.write( "\n" ); document.write( "need this answered tonight!!! thank you!! \r
\n" ); document.write( "\n" ); document.write( "(this is a really neat place!!)
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Algebra.Com's Answer #130554 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%28-3a%2Bb=4%2C-9a%2B5b=-1%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"-3%28-3a%2Bb%29=-3%284%29\" Multiply the both sides of the first equation by -3.\r
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\n" ); document.write( "\n" ); document.write( "\"9a-3b=-12\" 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%289a-3b=-12%2C-9a%2B5b=-1%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( "\"%289a-3b%29%2B%28-9a%2B5b%29=%28-12%29%2B%28-1%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%289a%2B-9a%29%2B%28-3b%2B5b%29=-12%2B-1\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0a%2B2b=-13\" Combine like terms. Notice how the x terms cancel out.\r
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\n" ); document.write( "\n" ); document.write( "\"2b=-13\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"b=%28-13%29%2F%282%29\" Divide both sides by \"2\" to isolate \"b\".\r
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\n" ); document.write( "\n" ); document.write( "\"9a-3b=-12\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"9a-3%28-13%2F2%29=-12\" Plug in \"b=-13%2F2\".\r
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\n" ); document.write( "\n" ); document.write( "\"9a%2B39%2F2=-12\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"2%289a%2B39%2Fcross%282%29%29=2%28-12%29\" Multiply both sides by the LCD \"2\" to clear any fractions.\r
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\n" ); document.write( "\n" ); document.write( "\"18a%2B39=-24\" Distribute and multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"18a=-24-39\" Subtract \"39\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"18a=-63\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"a=%28-63%29%2F%2818%29\" Divide both sides by \"18\" to isolate \"a\".\r
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\n" ); document.write( "\n" ); document.write( "\"a=-7%2F2\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \"a=-7%2F2\" and \"b=-13%2F2\".\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.
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