document.write( "Question 133088: solve by completing the square 2m^2-m-15=0? \n" ); document.write( "
Algebra.Com's Answer #97305 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"y=2+x%5E2-1+x-15\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B15=2+x%5E2-1+x\" Add \"15\" to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B15=2%28x%5E2%2B%28-1%2F2%29x%29\" Factor out the leading coefficient \"2\"\r
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\n" ); document.write( "\n" ); document.write( "Take half of the x coefficient \"-1%2F2\" to get \"-1%2F4\" (ie \"%281%2F2%29%28-1%2F2%29=-1%2F4\").\r
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\n" ); document.write( "\n" ); document.write( "Now square \"-1%2F4\" to get \"1%2F16\" (ie \"%28-1%2F4%29%5E2=%28-1%2F4%29%28-1%2F4%29=1%2F16\")\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B15=2%28x%5E2%2B%28-1%2F2%29x%2B1%2F16-1%2F16%29\" Now add and subtract this value inside the parenthesis. Doing both the addition and subtraction of \"1%2F16\" does not change the equation\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B15=2%28%28x-1%2F4%29%5E2-1%2F16%29\" Now factor \"x%5E2%2B%28-1%2F2%29x%2B1%2F16\" to get \"%28x-1%2F4%29%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B15=2%28x-1%2F4%29%5E2-2%281%2F16%29\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"y%2B15=2%28x-1%2F4%29%5E2-1%2F8\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=2%28x-1%2F4%29%5E2-1%2F8-15\" Now add \"%2B15\" to both sides to isolate y\r
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\n" ); document.write( "\n" ); document.write( "\"y=2%28x-1%2F4%29%5E2-121%2F8\" Combine like terms\r
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\n" ); document.write( "\n" ); document.write( "\"2%28x-1%2F4%29%5E2-121%2F8=0\" Now to solve for x, let \"y=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"2%28x-1%2F4%29%5E2=%2B121%2F8\" Add \"121%2F8\" to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-1%2F4%29%5E2=%28121%2F8%29%2F%282%29\" Divide both sides by \"2\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-1%2F4%29%5E2=121%2F16\" Reduce\r
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\n" ); document.write( "\n" ); document.write( " Take the square root of both sides\r
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\n" ); document.write( "\n" ); document.write( " Take the square root of 121 to get 11. Take the square root of 16 to get 4. \r
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\n" ); document.write( "\n" ); document.write( " Add \"1%2F4\" to both sides\r
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\n" ); document.write( "\n" ); document.write( "Break up the expression\r
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\n" ); document.write( "\n" ); document.write( " or \r
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\n" ); document.write( "\n" ); document.write( "Combine the fractions\r
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\n" ); document.write( "\n" ); document.write( " or \r
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\n" ); document.write( "\n" ); document.write( "Combine like terms\r
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\n" ); document.write( "\n" ); document.write( "Reduce\r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
\n" ); document.write( "\n" ); document.write( "So our solution is \r
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