STEP 1: Recall what is symmetry

https://www.learner.org/courses/learningmath/geometry/session7/part_a/index.html

The graph of a quadratic function is a parabola. 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

x -coordinate of the vertex is the equation of the axis of symmetry of the parabola.The axis of symmetry is given by the formula x = -\frac{b}{2a}

STEP 2: Find the axis of symmetry of y = x^{2}-4x + 2

Since the axis of symmetry is at x = -\frac{b}{2a},

plugging in the values of a = 1, b = -4 we get x = -\frac{-4}{2} = 2

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