Answer: It is an isometry.
The transformation is done over a line of reflection.
It flips a plane about a fixed line.
Explanation:
We know that on the coordinate plane , a reflection is a type of rigid transformation flips a shape across a given line without changing its shape and size of the figure.
It is said to be isometry because the original figure and its image after reflection are congruent .
Thus it does not change the size of the figure .