document.write( "Question 40249This question is from textbook College Algebra
\n" ); document.write( ": question is: f(x)=2x^2-x-1\r
\n" ); document.write( "\n" ); document.write( " List the y-intercept, if there is one, of the graph of f(x). \n" ); document.write( "
Algebra.Com's Answer #25614 by Nate(3500)\"\" \"About 
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f(x)=2x^2-x-1
\n" ); document.write( "The y-intercept is at \"-1\" because when you fill in zero for the \"x\", you get zero.
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"2x%5E2%2B-1x%2B-1+=+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=%28-1%29%5E2-4%2A2%2A-1=9\".
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\n" ); document.write( " Discriminant d=9 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--1%2B-sqrt%28+9+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%28-1%29%2Bsqrt%28+9+%29%29%2F2%5C2+=+1\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28-1%29-sqrt%28+9+%29%29%2F2%5C2+=+-0.5\"
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\n" ); document.write( " Quadratic expression \"2x%5E2%2B-1x%2B-1\" can be factored:
\n" ); document.write( " \"2x%5E2%2B-1x%2B-1+=+2%28x-1%29%2A%28x--0.5%29\"
\n" ); document.write( " Again, the answer is: 1, -0.5.\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-1+%29\"
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