document.write( "Question 966747: Can someone please help with these few question step by step? I work them out,but it doesn't add up.\r
\n" ); document.write( "\n" ); document.write( "8x^2-64=0 x=\r
\n" ); document.write( "\n" ); document.write( "0.7x^2=175 x= \r
\n" ); document.write( "\n" ); document.write( "4.8x^2=8 x=\r
\n" ); document.write( "\n" ); document.write( "2.56x^2=20 x=\r
\n" ); document.write( "\n" ); document.write( "x^2+8x=16 x=
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Algebra.Com's Answer #590879 by Alan3354(69443)\"\" \"About 
You can put this solution on YOUR website!
8x^2-64=0
\n" ); document.write( "8x^2 = 64
\n" ); document.write( "x^2 = 8
\n" ); document.write( "x = +/- sqrt(8)
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\n" ); document.write( "\n" ); document.write( "0.7x^2=175
\n" ); document.write( "x^2 = 250
\n" ); document.write( "etc
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\n" ); document.write( "\n" ); document.write( "4.8x^2=8 x=
\n" ); document.write( "Same as above
\n" ); document.write( "-----
\n" ); document.write( "2.56x^2=20 x=
\n" ); document.write( "Same as above
\n" ); document.write( "------
\n" ); document.write( "x^2+8x=16
\n" ); document.write( "x^2 + 8x - 16 = 0
\n" ); document.write( "\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"1x%5E2%2B8x%2B-16+=+0\") has the following solutons:
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\n" ); document.write( " \"x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
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\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
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\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%288%29%5E2-4%2A1%2A-16=128\".
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\n" ); document.write( " Discriminant d=128 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-8%2B-sqrt%28+128+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%288%29%2Bsqrt%28+128+%29%29%2F2%5C1+=+1.65685424949238\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%288%29-sqrt%28+128+%29%29%2F2%5C1+=+-9.65685424949238\"
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\n" ); document.write( " Quadratic expression \"1x%5E2%2B8x%2B-16\" can be factored:
\n" ); document.write( " \"1x%5E2%2B8x%2B-16+=+%28x-1.65685424949238%29%2A%28x--9.65685424949238%29\"
\n" ); document.write( " Again, the answer is: 1.65685424949238, -9.65685424949238.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B8%2Ax%2B-16+%29\"
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