To find the coordinates of the image point P of the given triangle after reflection across x - axis,
Rule for the reflection of a point (x, y) will be,
P(x, y) → P'(x, -y)
By applying the same rule in the graph attached,
Coordinates of a point P → (2, 1)
After reflection across x-axis, coordinates of the image point will be,
P(2, 1) → P'(2, -1)
Therefore, coordinates of the image point will be Option (A).
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