Choose the equation below whose axis of symmetry is x = 0.
y = x2 + 2x
y = x2 − 16x + 58
y = x2 + 2
y = x2 − 4x + 2

The axis of symmetry of a parabola is a vertical line that divides the parabola into two congruent halves. The axis of symmetry always passes through the vertex of the parabola. The x-coordinate of the vertex of the parabola can be found as

The equation x=0 represents the y-axis, therefore, parabola should be symmetric about the y-axis. This means that parabola vertex is placed on the y-axis. If parabola vertex is placed on the y-axis, then and

Only third parabola has b=0, then

correct choice is C.

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