document.write( "Question 7318: solve the following equation. express roots to the nearest hundredth.\r
\n" ); document.write( "\n" ); document.write( "2m^2-m-7=0
\n" ); document.write( "

Algebra.Com's Answer #4073 by ichudov(507)\"\" \"About 
You can put this solution on YOUR website!
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"am%5E2%2Bbm%2Bc=0\" (in our case \"2m%5E2%2B-1m%2B-7+=+0\") has the following solutons:
\n" ); document.write( "
\n" ); document.write( " \"m%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
\n" ); document.write( "
\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
\n" ); document.write( "
\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%28-1%29%5E2-4%2A2%2A-7=57\".
\n" ); document.write( "
\n" ); document.write( " Discriminant d=57 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--1%2B-sqrt%28+57+%29%29%2F2%5Ca\".
\n" ); document.write( "
\n" ); document.write( " \"m%5B1%5D+=+%28-%28-1%29%2Bsqrt%28+57+%29%29%2F2%5C2+=+2.13745860881769\"
\n" ); document.write( " \"m%5B2%5D+=+%28-%28-1%29-sqrt%28+57+%29%29%2F2%5C2+=+-1.63745860881769\"
\n" ); document.write( "
\n" ); document.write( " Quadratic expression \"2m%5E2%2B-1m%2B-7\" can be factored:
\n" ); document.write( " \"2m%5E2%2B-1m%2B-7+=+2%28m-2.13745860881769%29%2A%28m--1.63745860881769%29\"
\n" ); document.write( " Again, the answer is: 2.13745860881769, -1.63745860881769.\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-1%2Ax%2B-7+%29\"
\n" ); document.write( "
\n" ); document.write( "
\n" );