When a square is rotated 90 degrees, does its silhouette change?

When a square is rotated 90 degrees, does its silhouette change?

• A. Yes; it becomes a rotated square
• B. It becomes two separate shapes
• C. No; it remains the same
• D. It turns into a circle

Answer: (C)

Rotational symmetry means a shape can look the same after certain turns. A square has fourfold rotational symmetry, so turning it a quarter of a circle (90 degrees) makes its boundary line up exactly with the original. The silhouette—the outer outline—stays the same square with four equal sides and right angles. A rigid rotation doesn’t create new parts or morph the shape into a circle, so the outline remains unchanged.

Rotational symmetry means a shape can look the same after certain turns. A square has fourfold rotational symmetry, so turning it a quarter of a circle (90 degrees) makes its boundary line up exactly with the original. The silhouette—the outer outline—stays the same square with four equal sides and right angles. A rigid rotation doesn’t create new parts or morph the shape into a circle, so the outline remains unchanged.