The video tutorial introduces two-dimensional (2D) shapes, highlighting their flat nature and common examples like triangles, circles, rectangles, and squares. It explains how 2D shapes can be defined by their sides, with some having straight sides and others not. The concept of vertices is introduced, explaining that some shapes have corners while others do not. The tutorial also covers the idea of closed shapes, demonstrating how tracing a shape can help determine if it is closed. Overall, the video provides a foundational understanding of 2D shapes, their characteristics, and how to identify them.

Which of the following is a common feature of all 2D shapes?

• They all have three sides.

• They all have corners.

• They are all flat.

• They are all round.

Why is a baseball not considered a 2D shape?

• It is a polygon.

• It has no corners.

• It has straight sides.

• It is not flat.

How would you describe the sides of a triangle?

• Curved lines

• Straight lines

• Wavy lines

• No lines

Which 2D shape has no straight sides?

• Square

• Rectangle

• Circle

• Triangle

How many sides does a rectangle have?

• Three

• Four

• Five

• Six

What is a vertex in the context of 2D shapes?

• A corner

• A straight side

• A flat surface

• A curved line

How many vertices does a triangle have?

• Two

• Three

• Four

• Five

Which shape has no vertices?

• Square

• Triangle

• Rectangle

• Circle

What indicates that a 2D shape is closed?

• It is not flat.

• All sides are connected.

• It has no vertices.

• It has no sides.

What happens when you trace a closed 2D shape?

• You find a vertex.

• You create a new shape.

• You come back to the starting point.

• You end at a different point.