document.write( "Question 295725: This is how I solved the problem. Where did I mis-calculate?
\n" ); document.write( " $\"x%5E2-3x-28=0\"$
\n" ); document.write( "-3(-3)+- sq.rt(-3)^2-4`1`(-28) 3 +- sq.rt.729 3+9
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\n" ); document.write( "\n" ); document.write( "x= 3-27 = -24 = -12 or x= 3+27 = 30 = 15
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Algebra.Com's Answer #213147 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 $\"x%5E2-3%2Ax-28=0\"$ ( notice $\"a=1\"$ , $\"b=-3\"$ , and $\"c=-28\"$ )
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\n" ); document.write( " $\"x+=+%28--3+%2B-+sqrt%28+%28-3%29%5E2-4%2A1%2A-28+%29%29%2F%282%2A1%29\"$ Plug in a=1, b=-3, and c=-28
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\n" ); document.write( " $\"x+=+%283+%2B-+sqrt%28+%28-3%29%5E2-4%2A1%2A-28+%29%29%2F%282%2A1%29\"$ Negate -3 to get 3
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\n" ); document.write( " $\"x+=+%283+%2B-+sqrt%28+9-4%2A1%2A-28+%29%29%2F%282%2A1%29\"$ Square -3 to get 9 (note: remember when you square -3, you must square the negative as well. This is because $\"%28-3%29%5E2=-3%2A-3=9\"$ .)
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\n" ); document.write( " $\"x+=+%283+%2B-+sqrt%28+9%2B112+%29%29%2F%282%2A1%29\"$ Multiply $\"-4%2A-28%2A1\"$ to get $\"112\"$
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\n" ); document.write( " $\"x+=+%283+%2B-+sqrt%28+121+%29%29%2F%282%2A1%29\"$ Combine like terms in the radicand (everything under the square root)
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\n" ); document.write( " $\"x+=+%283+%2B-+11%29%2F%282%2A1%29\"$ 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( " $\"x+=+%283+%2B-+11%29%2F2\"$ 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( " $\"x+=+%283+%2B+11%29%2F2\"$ or $\"x+=+%283+-+11%29%2F2\"$
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\n" ); document.write( " Lets look at the first part:
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\n" ); document.write( " $\"x=%283+%2B+11%29%2F2\"$
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\n" ); document.write( " $\"x=14%2F2\"$ Add the terms in the numerator
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\n" ); document.write( " $\"x=7\"$ Divide
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\n" ); document.write( " So one answer is
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\n" ); document.write( " $\"x=7\"$
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\n" ); document.write( " Now lets look at the second part:
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\n" ); document.write( " $\"x=%283+-+11%29%2F2\"$
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\n" ); document.write( " $\"x=-8%2F2\"$ Subtract the terms in the numerator
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\n" ); document.write( " $\"x=-4\"$ Divide
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\n" ); document.write( " So another answer is
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\n" ); document.write( " $\"x=-4\"$
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\n" ); document.write( " So our solutions are:
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\n" ); document.write( " $\"x=7\"$ or $\"x=-4\"$
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