document.write( "Question 700974: Use the Quadratic Formula to solve the equation.
\n" ); document.write( "–x^2 + 7x = 8 \n" ); document.write( "
Algebra.Com's Answer #432109 by MathLover1(20849)\"\" \"About 
You can put this solution on YOUR website!
\"-x%5E2+%2B+7x+=+8\"....write it in standard form \"ax%5E2%2Bbx%2Bc=0\"\r
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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%2B7%2Ax-8=0\" ( notice \"a=-1\", \"b=7\", and \"c=-8\")
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\n" ); document.write( " \"x+=+%28-7+%2B-+sqrt%28+%287%29%5E2-4%2A-1%2A-8+%29%29%2F%282%2A-1%29\" Plug in a=-1, b=7, and c=-8
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\n" ); document.write( " \"x+=+%28-7+%2B-+sqrt%28+49-4%2A-1%2A-8+%29%29%2F%282%2A-1%29\" Square 7 to get 49
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\n" ); document.write( " \"x+=+%28-7+%2B-+sqrt%28+49%2B-32+%29%29%2F%282%2A-1%29\" Multiply \"-4%2A-8%2A-1\" to get \"-32\"
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\n" ); document.write( " \"x+=+%28-7+%2B-+sqrt%28+17+%29%29%2F%282%2A-1%29\" Combine like terms in the radicand (everything under the square root)
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\n" ); document.write( " \"x+=+%28-7+%2B-+sqrt%2817%29%29%2F%282%2A-1%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+=+%28-7+%2B-+sqrt%2817%29%29%2F-2\" 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+=+%28-7+%2B+sqrt%2817%29%29%2F-2\" or \"x+=+%28-7+-+sqrt%2817%29%29%2F-2\"
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\n" ); document.write( " Now break up the fraction
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\n" ); document.write( " \"x=-7%2F-2%2Bsqrt%2817%29%2F-2\" or \"x=-7%2F-2-sqrt%2817%29%2F-2\"
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\n" ); document.write( " Simplify
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\n" ); document.write( " \"x=7%2F2-sqrt%2817%29%2F2\" or \"x=7%2F2%2Bsqrt%2817%29%2F2\"
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\n" ); document.write( " So the solutions are:
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\n" ); document.write( " \"x=7%2F2-sqrt%2817%29%2F2\" or \"x=7%2F2%2Bsqrt%2817%29%2F2\"
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