Rotational Symmetry Concepts and Applications

The video tutorial explores rotational symmetry through three examples: a geometric figure, the letter N, and a checkerboard. For each example, it determines if the figure has rotational symmetry, calculates the angle of symmetry, and identifies the number of rotations possible. Example A shows a figure with five vertices, resulting in five rotations and a 72-degree angle. Example B examines the letter N, which has two rotations and a 180-degree angle. Example C analyzes a checkerboard, which has four rotations and a 90-degree angle.

What is the first step in determining if a figure has rotational symmetry?

• Count the number of vertices.

• Check if the figure has equal sides.

• Rotate the figure around its center point.

• Measure the angles between vertices.

How many vertices does the given figure in Example A have?

• Three

• Six

• Four

• Five

How many times can the figure in Example A be rotated to demonstrate rotational symmetry?

• Five times

• Six times

• Three times

• Four times

What is the angle of symmetry for the figure in Example A?

• 120 degrees

• 90 degrees

• 72 degrees

• 60 degrees

Does the letter N have rotational symmetry?

• Yes, it has rotational symmetry.

• No, it does not have rotational symmetry.

• Only when rotated 90 degrees.

• Only when rotated 45 degrees.

How many times can the letter N be rotated to demonstrate rotational symmetry?

• One time

• Two times

• Three times

• Four times

What is the angle of symmetry for the letter N?

• 180 degrees

• 120 degrees

• 360 degrees

• 90 degrees

Does the checkerboard have rotational symmetry?

• Yes, it has rotational symmetry.

• Only when rotated 45 degrees.

• No, it does not have rotational symmetry.

• Only when rotated 60 degrees.

How many times can the checkerboard be rotated to demonstrate rotational symmetry?

• Four times

• Five times

• Three times

• Two times

What is the angle of symmetry for the checkerboard?

• 120 degrees

• 90 degrees

• 60 degrees

• 45 degrees