document.write( "Question 858471: if the quadratic formula is used to find the roots of the equation x2 - 6x - 19 =0 ((the 2 is the second power))\r
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Algebra.Com's Answer #517214 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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Solved by pluggable solver: Quadratic Formula
Let's use the quadratic formula to solve for x:

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\n" ); document.write( " Starting with the general quadratic
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\n" ); document.write( " \"ax%5E2%2Bbx%2Bc=0\"
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\n" ); document.write( " the general solution using the quadratic equation is:
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\n" ); document.write( " \"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29\"
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\n" ); document.write( " So lets solve \"x%5E2-6%2Ax-19=0\" ( notice \"a=1\", \"b=-6\", and \"c=-19\")
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\n" ); document.write( " \"x+=+%28--6+%2B-+sqrt%28+%28-6%29%5E2-4%2A1%2A-19+%29%29%2F%282%2A1%29\" Plug in a=1, b=-6, and c=-19
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\n" ); document.write( " \"x+=+%286+%2B-+sqrt%28+%28-6%29%5E2-4%2A1%2A-19+%29%29%2F%282%2A1%29\" Negate -6 to get 6
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\n" ); document.write( " \"x+=+%286+%2B-+sqrt%28+36-4%2A1%2A-19+%29%29%2F%282%2A1%29\" Square -6 to get 36 (note: remember when you square -6, you must square the negative as well. This is because \"%28-6%29%5E2=-6%2A-6=36\".)
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\n" ); document.write( " \"x+=+%286+%2B-+sqrt%28+36%2B76+%29%29%2F%282%2A1%29\" Multiply \"-4%2A-19%2A1\" to get \"76\"
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\n" ); document.write( " \"x+=+%286+%2B-+sqrt%28+112+%29%29%2F%282%2A1%29\" Combine like terms in the radicand (everything under the square root)
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\n" ); document.write( " \"x+=+%286+%2B-+4%2Asqrt%287%29%29%2F%282%2A1%29\" Simplify the square root (note: If you need help with simplifying the square root, check out this solver)
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\n" ); document.write( " \"x+=+%286+%2B-+4%2Asqrt%287%29%29%2F2\" Multiply 2 and 1 to get 2
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\n" ); document.write( " So now the expression breaks down into two parts
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\n" ); document.write( " \"x+=+%286+%2B+4%2Asqrt%287%29%29%2F2\" or \"x+=+%286+-+4%2Asqrt%287%29%29%2F2\"
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\n" ); document.write( " Now break up the fraction
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\n" ); document.write( " \"x=%2B6%2F2%2B4%2Asqrt%287%29%2F2\" or \"x=%2B6%2F2-4%2Asqrt%287%29%2F2\"
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\n" ); document.write( " Simplify
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\n" ); document.write( " \"x=3%2B2%2Asqrt%287%29\" or \"x=3-2%2Asqrt%287%29\"
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\n" ); document.write( " So the solutions are:
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\n" ); document.write( " \"x=3%2B2%2Asqrt%287%29\" or \"x=3-2%2Asqrt%287%29\"
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