document.write( "Question 140894: please help use the quadratic formula x= -b+ (small dash under plus sign)sqrt (b^2-4ac)/2a find the roots of the equation x^2-4/3x+1/3=0 \n" ); document.write( "
Algebra.Com's Answer #102557 by jim_thompson5910(35256)\"\" \"About 
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\"x%5E2-%284%2F3%29x%2B1%2F3=0\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"3%28x%5E2-%284%2Fcross%283%29%29x%2B1%2Fcross%283%29%29=3%2A0\" Multiply both sides by the LCD 3. This will cancel out the denominators and clear the fractions\r
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\n" ); document.write( "\n" ); document.write( "\"3x%5E2-4x%2B1=0\" Distribute and multiply\r
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\n" ); document.write( "\n" ); document.write( "Now let's use the quadratic formula to solve for x:\r
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\n" ); document.write( "\n" ); document.write( "Starting with the general quadratic\r
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\n" ); document.write( "\n" ); document.write( "\"ax%5E2%2Bbx%2Bc=0\"\r
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\n" ); document.write( "\n" ); document.write( "the general solution using the quadratic equation is:\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29\"\r
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\n" ); document.write( "\n" ); document.write( "So lets solve \"3%2Ax%5E2-4%2Ax%2B1=0\" ( notice \"a=3\", \"b=-4\", and \"c=1\")\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28--4+%2B-+sqrt%28+%28-4%29%5E2-4%2A3%2A1+%29%29%2F%282%2A3%29\" Plug in a=3, b=-4, and c=1\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%284+%2B-+sqrt%28+%28-4%29%5E2-4%2A3%2A1+%29%29%2F%282%2A3%29\" Negate -4 to get 4\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%284+%2B-+sqrt%28+16-4%2A3%2A1+%29%29%2F%282%2A3%29\" Square -4 to get 16 (note: remember when you square -4, you must square the negative as well. This is because \"%28-4%29%5E2=-4%2A-4=16\".)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%284+%2B-+sqrt%28+16%2B-12+%29%29%2F%282%2A3%29\" Multiply \"-4%2A1%2A3\" to get \"-12\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%284+%2B-+sqrt%28+4+%29%29%2F%282%2A3%29\" Combine like terms in the radicand (everything under the square root)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%284+%2B-+2%29%2F%282%2A3%29\" Simplify the square root (note: If you need help with simplifying the square root, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%284+%2B-+2%29%2F6\" Multiply 2 and 3 to get 6\r
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\n" ); document.write( "\n" ); document.write( "So now the expression breaks down into two parts\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%284+%2B+2%29%2F6\" or \"x+=+%284+-+2%29%2F6\"\r
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\n" ); document.write( "\n" ); document.write( "Lets look at the first part:\r
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\n" ); document.write( "\n" ); document.write( "\"x=%284+%2B+2%29%2F6\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=6%2F6\" Add the terms in the numerator\r
\n" ); document.write( "\n" ); document.write( "\"x=1\" Divide\r
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\n" ); document.write( "\n" ); document.write( "So one answer is\r
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\n" ); document.write( "\n" ); document.write( "Now lets look at the second part:\r
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\n" ); document.write( "\n" ); document.write( "\"x=%284+-+2%29%2F6\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=2%2F6\" Subtract the terms in the numerator\r
\n" ); document.write( "\n" ); document.write( "\"x=1%2F3\" Divide\r
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\n" ); document.write( "\n" ); document.write( "So another answer is\r
\n" ); document.write( "\n" ); document.write( "\"x=1%2F3\"\r
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\n" ); document.write( "\n" ); document.write( "So our solutions are:\r
\n" ); document.write( "\n" ); document.write( "\"x=1\" or \"x=1%2F3\"\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph \"3%2Ax%5E2-4%2Ax%2B1\", we get:\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+500%2C+500%2C+-9%2C+11%2C+-9%2C+11%2C3%2Ax%5E2%2B-4%2Ax%2B1%29+\"\r
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\n" ); document.write( "\n" ); document.write( "and we can see that the roots are \"x=1\" and \"x=1%2F3\". This verifies our answer\r
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