When we rotate a figure and there is no change in the shape of the figure then it has rotational symmetry.
We know that the order of rotation for a square is 4.
Hence, we have [tex]\frac{360}{4} =90^{\circ}[/tex]
Thus, the angle of rotational symmetry of square are
[tex]90^{\circ}, 180^{\circ}, 270^{\circ}[/tex]
Hence, the minimum angle of rotational symmetry is [tex]90^{\circ}[/tex]
Therefore, the minimum angle of rotational symmetry for a square is 90 degrees.
