About Open and Closed Shapes
What are Shapes?
In geometry, shapes are defined as objects with specific boundaries or outlines. Shapes can be classified by their dimensions as two dimensional (2D) or three dimensional (3D) shapes. Shapes are also classified as open and closed shapes, which is the topic of this article.
What is an Open Shape?
An open shape is defined as the shapes in which the line segments or curves do not connect at their ends. Here are a few examples of open shapes.
What is a Closed Shape?
A closed shape is defined as a shape that starts and ends at the same point. In other words, a closed shape does not have an open end. Here are some examples of closed shapes.
Solved Examples
Example 1: Identify whether the following shapes are open or closed shapes.
Solution:
In the image, there are both open and closed shapes.
The first two shapes are open as in both shapes, the starting and end point are not the same. Hence, they are open shapes.
The next three shapes are examples of different geometrical shapes such as heptagon (seven sided polygon), octagon (eight sided polygon) and a circle (a closed curve). All these three shapes are closed because their line segments and the curve are connected with each other and the start and end point are the same or can not be distinguished.
Example 2: Matthew came across these objects while going to school. Can you help him identify these objects as open or closed shapes?
Solution:
Classifying these objects depends on their shape.
The first item is a coiled rope where the ends do not meet with each other. Hence, this is an open shape.
The second item is a paper clip which has two ends. The ends do not connect as this is an open shape.
The third item is a window and as the sides are connected to one another, it is a closed shape.
Example 3: Is the shape in the following image open or closed?
Solution:
The shape in the image is enclosed by all sides and the start and end point is the same. As a result, this is a closed shape.
A polygon is a two-dimensional figure made up of line segments.
A hexagon is a closed figure with six sides. It is regarded as a polygon as well.
Yes, the letter ‘U’ is an example of an open shape as this curved letter has two endpoints that are not connected.
The digits ‘0’ and ‘8’ are closed and their start and end points are not distinct. So they can be called closed shapes.