Describe and correct the error. Please help!

Answer:
the rotation angle is double the angle between the lines
Step-by-step explanation:
The Reflections in Intersecting Lines Theorem will tell you that the effective angle of rotation is double the angle between the intersecting lines. Here, the figure is effectively rotated 144°, not 72°. If a 72° rotation is desired, the lines need to intersect at an angle of 36°.