document.write( "Question 302443: 2b to the 2 power -15b -7 =0 \n" ); document.write( "
Algebra.Com's Answer #216849 by richwmiller(17219)\"\" \"About 
You can put this solution on YOUR website!
2b^2-15b-7=0\r
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ab%5E2%2Bbb%2Bc=0\" (in our case \"2b%5E2%2B-15b%2B-7+=+0\") has the following solutons:
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\n" ); document.write( " \"b%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=%28-15%29%5E2-4%2A2%2A-7=281\".
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\n" ); document.write( " Discriminant d=281 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--15%2B-sqrt%28+281+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"b%5B1%5D+=+%28-%28-15%29%2Bsqrt%28+281+%29%29%2F2%5C2+=+7.94076365356005\"
\n" ); document.write( " \"b%5B2%5D+=+%28-%28-15%29-sqrt%28+281+%29%29%2F2%5C2+=+-0.440763653560053\"
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\n" ); document.write( " Quadratic expression \"2b%5E2%2B-15b%2B-7\" can be factored:
\n" ); document.write( " \"2b%5E2%2B-15b%2B-7+=+2%28b-7.94076365356005%29%2A%28b--0.440763653560053%29\"
\n" ); document.write( " Again, the answer is: 7.94076365356005, -0.440763653560053.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+2%2Ax%5E2%2B-15%2Ax%2B-7+%29\"
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