DEFINITION AND PROPERTIES OF A POLYGON | FIRST QUARTER GRADE 7 MATATAG [TAGALOG MATH TUTORIAL]

Summary

In this educational video, learners are introduced to polygons, focusing on their definition and characteristics. The instructor uses various examples, such as road signs and everyday objects, to engage the audience in recognizing shapes. Through an activity, students are encouraged to identify polygons, followed by a detailed explanation of the criteria for a shape to be considered a polygon: it must be closed, flat, and bounded by line segments that meet only at their endpoints. The video concludes with a recap of these points, ensuring viewers grasp the concept of polygons.

Takeaways

• 😀 A polygon is a closed, flat (2D) shape made up of straight line segments.
• 😀 Polygons meet only at their endpoints, meaning no other intersections are allowed within the shape.
• 😀 The key characteristics of polygons are: being closed, flat, made of line segments, and having endpoints that intersect.
• 😀 Real-world objects, like road signs, are often polygons, such as stop signs and pedestrian crossing signs.
• 😀 Some shapes, like circles, are not polygons because they are not made of straight lines and do not meet at endpoints.
• 😀 3D objects, like a Rubik's Cube or a ball, are not polygons because they are not flat (2D).
• 😀 Everyday objects like paper, toys, and instruments (such as the triangle) are made up of shapes, many of which are polygons.
• 😀 A polygon must be a flat (2D) figure; 3D shapes like spheres or cubes do not qualify as polygons.
• 😀 During the activity in the lesson, students are asked to identify which of various figures are polygons based on their characteristics.
• 😀 The lesson emphasizes critical thinking by asking students to reflect on the properties of polygons and non-polygons, using both theoretical and real-world examples.

Q & A

What is a polygon?

A polygon is a closed plane figure bounded by line segments that meet only at their endpoints.

What are the four criteria that define a polygon?

The four criteria for a shape to be considered a polygon are: 1) It must be a closed figure, 2) It must be a flat or two-dimensional shape, 3) It must be bounded by line segments, and 4) The line segments must meet only at their endpoints.

Why is a circle not considered a polygon?

A circle is not considered a polygon because it is not made up of straight line segments, and its boundary is a curve, not a series of straight lines. Additionally, a circle does not have endpoints that meet, which is a requirement for polygons.

Can a three-dimensional shape be a polygon?

No, a three-dimensional shape cannot be a polygon. A polygon must be a two-dimensional or flat shape, while three-dimensional shapes like spheres or cubes are not considered polygons.

Why is the Rubik’s Cube not a polygon?

The Rubik’s Cube is not a polygon because it is a three-dimensional object, not a flat or two-dimensional figure.

What makes a triangle a polygon?

A triangle is a polygon because it is a closed figure with three straight line segments that meet only at their endpoints. It satisfies all four criteria of a polygon.

Is a rectangle considered a polygon? Why or why not?

Yes, a rectangle is considered a polygon because it is a closed, flat figure bounded by four straight line segments that meet only at their endpoints.

What is the difference between a polygon and a non-polygon?

A polygon is a closed, flat figure with straight line segments meeting only at their endpoints, while a non-polygon either does not meet these criteria (such as being three-dimensional or having curved sides) or has line segments that do not meet at their endpoints.

Why is an hourglass shape not considered a polygon?

An hourglass shape is not considered a polygon because while it is a closed figure and bounded by line segments, the line segments intersect at multiple endpoints, which violates the rule that line segments in a polygon should only meet at one endpoint.

How can we differentiate between polygons and non-polygons when looking at various shapes?

To differentiate, check if the shape is closed, flat, and made up of straight line segments that meet only at their endpoints. If any of these criteria are not met, the shape is not a polygon.