document.write( "Question 110955: find the x-intercepts
\n" ); document.write( "y=x^2-3x-1 \n" ); document.write( "
Algebra.Com's Answer #80928 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-1=0\" ( notice \"a=1\", \"b=-3\", and \"c=-1\")
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\n" ); document.write( " \"x+=+%28--3+%2B-+sqrt%28+%28-3%29%5E2-4%2A1%2A-1+%29%29%2F%282%2A1%29\" Plug in a=1, b=-3, and c=-1
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\n" ); document.write( " \"x+=+%283+%2B-+sqrt%28+%28-3%29%5E2-4%2A1%2A-1+%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-1+%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%2B4+%29%29%2F%282%2A1%29\" Multiply \"-4%2A-1%2A1\" to get \"4\"
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\n" ); document.write( " \"x+=+%283+%2B-+sqrt%28+13+%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-+sqrt%2813%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+=+%283+%2B-+sqrt%2813%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+=+%283+%2B+sqrt%2813%29%29%2F2\" or \"x+=+%283+-+sqrt%2813%29%29%2F2\"
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\n" ); document.write( " Now break up the fraction
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\n" ); document.write( " \"x=%2B3%2F2%2Bsqrt%2813%29%2F2\" or \"x=%2B3%2F2-sqrt%2813%29%2F2\"
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\n" ); document.write( " Simplify
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\n" ); document.write( " \"x=3%2F2%2Bsqrt%2813%29%2F2\" or \"x=3%2F2-sqrt%2813%29%2F2\"
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\n" ); document.write( " So the solutions are:
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\n" ); document.write( " \"x=3%2F2%2Bsqrt%2813%29%2F2\" or \"x=3%2F2-sqrt%2813%29%2F2\"
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