Answer: Choice A
The axis of symmetry for the function is x = 0.
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Explanation:
The vertex is on the axis of symmetry. Since the vertex is on the y axis, this means the y axis itself is the axis of symmetry. The y axis is represented by the equation x = 0. Every point on the y axis has an x coordinate of 0. Example points are (0,2) and (0,5).
This parabola may have 0 roots, 1 root, or 2 roots.
1) Add x to -2x, which is -x
2) Subtract 3 to 5, which is 2
Answer) A
Answer is 
dm².
In order to calculate the area of the board that can be seen, we need to calculate the area of the the rectangular board and the circular frame. The difference of both's area is the required answer.
Refer to the attachment for step by step solution. :)
