document.write( "Question 745985: This problem is to graph the Quadratic Function y= -2Xsquared + 4X+1\r
\n" ); document.write( "\n" ); document.write( "I have tried this problem many times and keep ending up with
\n" ); document.write( "Vertex=(1,-1)
\n" ); document.write( "Y-int=(0,1)
\n" ); document.write( "X-int=(-2.22,0),(.22,0)\r
\n" ); document.write( "\n" ); document.write( "Both x intercepts are to the left of the vertex and the y intercept in in between the two x intercepts, so no symmetric parabola can be graphed.
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\n" ); document.write( "I am not sure what I am doing wrong, but it probably involved solving for the vertex. I am using the -b/2a formulas and standard x/y int method. \r
\n" ); document.write( "\n" ); document.write( "Keep in mind, my instructor has written his own workbook, and the equation may have made a mistake.\r
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Algebra.Com's Answer #454098 by savvyhush23(50)\"\" \"About 
You can put this solution on YOUR website!
First solve the equation: \"y=-2x%5E2+%2B+4x%2B1\"
\n" ); document.write( "Since the squared term is x, equate the system in x, thus,
\n" ); document.write( "\"2x%5E2-4x%2By-1=0\", completing the square
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\n" ); document.write( "\"2x%5E2-4x%2B2%2By-1=2\", add two both side
\n" ); document.write( "\"2%28x%5E2-2x%2B1%29=-y%2B3\",
\n" ); document.write( "\"%28x%5E2-1%29%5E2=%28-1%2F2%29%28y-3%29\"
\n" ); document.write( "The parabola is facing downward,
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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%2B4x%2B1+=+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=%284%29%5E2-4%2A-2%2A1=24\".
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\n" ); document.write( " Discriminant d=24 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-4%2B-sqrt%28+24+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%284%29%2Bsqrt%28+24+%29%29%2F2%5C-2+=+-0.224744871391589\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%284%29-sqrt%28+24+%29%29%2F2%5C-2+=+2.22474487139159\"
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\n" ); document.write( " Quadratic expression \"-2x%5E2%2B4x%2B1\" can be factored:
\n" ); document.write( " \"-2x%5E2%2B4x%2B1+=+-2%28x--0.224744871391589%29%2A%28x-2.22474487139159%29\"
\n" ); document.write( " Again, the answer is: -0.224744871391589, 2.22474487139159.\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%2B4%2Ax%2B1+%29\"

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\n" ); document.write( "so, the vertex:(1,3)
\n" ); document.write( "x-intercept: (-2.22,0),(0.22,0)
\n" ); document.write( "y-intercept: (0,1)
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