A line of symmetry<span> for a graph. The two sides of a graph on either side of the </span>axis of symmetry<span> look like mirror images of each other. Example: This is a graph of the parabola y = x</span>2<span> – 4x + 2 together with its </span>axis of symmetry<span> x = 2. The</span>axis of symmetry<span> is the red vertical line.
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