document.write( "Question 536440: 2(8x+1)^2=90\r
\n" ); document.write( "\n" ); document.write( "Solve using quadratic formula
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Algebra.Com's Answer #352352 by Maths68(1474)\"\" \"About 
You can put this solution on YOUR website!
\"2%288x%2B1%29%5E2=90\"
\n" ); document.write( "Divide by 2 both sides
\n" ); document.write( "\"2%288x%2B1%29%5E2%2F2=90%2F2\"
\n" ); document.write( "\"cross%282%29%288x%2B1%29%5E2%2F2=cross%2890%29%2Fcross%282%29\"
\n" ); document.write( "\"%288x%2B1%29%5E2=45\"
\n" ); document.write( "\"64x%5E2%2B16x%2B1=45\"
\n" ); document.write( "\"64x%5E2%2B16x%2B1-45=0\"
\n" ); document.write( "\"64x%5E2%2B16x-44=0\"
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"64x%5E2%2B16x%2B-44+=+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=%2816%29%5E2-4%2A64%2A-44=11520\".
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\n" ); document.write( " Discriminant d=11520 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-16%2B-sqrt%28+11520+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%2816%29%2Bsqrt%28+11520+%29%29%2F2%5C64+=+0.713525491562421\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%2816%29-sqrt%28+11520+%29%29%2F2%5C64+=+-0.963525491562421\"
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\n" ); document.write( " Quadratic expression \"64x%5E2%2B16x%2B-44\" can be factored:
\n" ); document.write( " \"64x%5E2%2B16x%2B-44+=+64%28x-0.713525491562421%29%2A%28x--0.963525491562421%29\"
\n" ); document.write( " Again, the answer is: 0.713525491562421, -0.963525491562421.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+64%2Ax%5E2%2B16%2Ax%2B-44+%29\"

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