Rotation and Properties of Triangles

The video tutorial covers practice problem four from lesson nine, focusing on the rotation of triangle ABC around point D, the center of rotation. It explains the properties of rigid transformations, ensuring angles and side lengths remain unchanged. The tutorial details how to calculate rotation degrees using a protractor and describes the path of rotation for points A, B, and C. The final position of the triangle is discussed, emphasizing the equivalence of angles and side lengths due to the rigid transformation.

What is the center of rotation for triangle ABC in the practice problem?

• Point D

• Point C

• Point A

• Point B

Which of the following remains unchanged during a rigid transformation?

• The position of the triangle

• The color of the triangle

• The type of transformation

• The size of angles

How many degrees does point A rotate to reach A'?

• 90 degrees

• 120 degrees

• 180 degrees

• 360 degrees

What tool is used to measure the degrees of rotation?

• Ruler

• Compass

• Protractor

• Calculator

If point B rotates to B', what is the angle of rotation?

• 360 degrees

• 180 degrees

• 120 degrees

• 90 degrees

Which path does point C follow during the rotation?

• A straight line

• A random path

• A circular path

• A zigzag path

What is the length of BC in the original triangle?

• 5 units

• 4 units

• 2 units

• 3 units

After the rotation, what is the length of B'C'?

• 2 units

• 3 units

• 4 units

• 5 units

What is the measure of angle B in the original triangle?

• 60 degrees

• 45 degrees

• 50 degrees

• 52 degrees

What is the measure of angle C in the original triangle?

• 45 degrees

• 52 degrees

• 60 degrees

• 50 degrees