Edges in Geometry
In geometry, an edge is a line segment where two faces of a solid figure meet. It is the boundary line of a face of a solid figure. For example, a cube has 12 edges, as each of its 6 faces is bounded by 2 edges.
Properties of Edges
The following are important properties of edges:
- An edge is a straight line segment.
- Edges are formed by the intersection of two faces of a solid figure.
- Edges have a length, which is the distance between the two vertices where they meet.
- Each edge of a solid figure is a part of two faces.
Examples of Edges
Here are some examples of solid figures and their respective number of edges:
- Cube: 12 edges
- Cylinder: 2 edges (the two circular bases)
- Tetrahedron: 6 edges
- Rectangular Prism: 12 edges
Study Guide
When studying edges in geometry, it's important to keep the following points in mind:
- Understand the definition of an edge as a line segment where two faces of a solid figure meet.
- Be able to identify and count the number of edges in different solid figures.
- Recognize the properties of edges, including their straightness, length, and the number of faces they are a part of.
- Practice visualizing and sketching the edges of various 3-dimensional shapes to reinforce your understanding.
Understanding edges is crucial for solving problems related to solid figures and their properties in geometry.
.◂Math Worksheets and Study Guides Eighth Grade. Real numbers
Study Guide
Real numbers 
Worksheet/Answer key
Real numbers Worksheet/Answer key
Real numbers Worksheet/Answer key
Real numbers Worksheet/Answer key
Real numbers
Worksheet/Answer keyWorksheet/Answer keyWorksheet/Answer keyWorksheet/Answer keyThe resources above cover the following skills:
The Number System
Know that there are numbers that are not rational, and approximate them by rational numbers.
Know that numbers that are not rational are called irrational. Understand informally that every number has a decimal expansion; for rational numbers show that the decimal expansion repeats eventually, and convert a decimal expansion which repeats eventually into a rational number. [8-NS1]
Expressions and Equations
Work with radicals and integer exponents.
Use square root and cube root symbols to represent solutions to equations of the form x^2 = p and x^3 = p, where p is a positive rational number. Evaluate square roots of small perfect squares and cube roots of small perfect cubes. Know that √2 is irrational. [8-EE2]