Question

Which of the following geometrical shape do not show rotational symmetry?

• A. Equilateral triangle
• B. Rectangle
• C. Regular Pentagon
• D. Scalane triangle

Answer 1

The correct option is D Scalane triangle

When we rotate an equilateral triangle by ${60}^{\text{o}},$ we get the equilateral triangle of same shape and size as it was before the rotation.

When we rotate a rectangle by ${180}^{\text{o}},$ we get the rectangle of same shape and size as it was before the rotation.

When we rotate a regular pentagon by ${72}^{\text{o}},$ we get the pentagon of same shape and size as it was before the rotation.
When we rotate a scalene triangle by any angle (less than ${360}^{\text{o}}$), we do not get the scalene triangle of same shape and size as it was before the rotation.