Question 745985: This problem is to graph the Quadratic Function y= -2Xsquared + 4X+1
I have tried this problem many times and keep ending up with
Vertex=(1,-1)
Y-int=(0,1)
X-int=(-2.22,0),(.22,0)
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.
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.
Keep in mind, my instructor has written his own workbook, and the equation may have made a mistake.
Answer by savvyhush23(50)   (Show Source):
You can put this solution on YOUR website! First solve the equation: 
Since the squared term is x, equate the system in x, thus,
 , completing the square
 , add two both side
 ,
The parabola is facing downward,
| Solved by pluggable solver: SOLVE quadratic equation with variable |
Quadratic equation  (in our case  ) has the following solutons:
For these solutions to exist, the discriminant  should not be a negative number.
First, we need to compute the discriminant :  .
Discriminant d=24 is greater than zero. That means that there are two solutions:  .
Quadratic expression  can be factored:
Again, the answer is: -0.224744871391589, 2.22474487139159.
Here's your graph:
 |
.
.
so, the vertex:(1,3)
x-intercept: (-2.22,0),(0.22,0)
y-intercept: (0,1)
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