If you're seeing this message, it means we're having trouble loading external resources on our website.

If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked.

## Geometry 218-221

### Unit 2: Lesson 1

Geometric solids (3D shapes)

# Counting faces and edges of 3D shapes

Sal identifies the faces and edges on various 3D shapes.

## Want to join the conversation?

• are vertices the same as edges
• No, vertices are like corners where three faces meet, with the exception of the apex, in which 4 or more faces meet in a pyramid.
• how can i identify faces and edges of a sphere? maybe its silly to ask but i am curious.
• A face is a flat surface on a solid, and edges are the lines at which faces meet, and a vertex is the point at which when three or more edges meet. A sphere has no flat surfaces, so it has no faces. Since it doesn't have faces, it can't have edges, or vertices.
• But what are vertices?
• Vertices are basically corners where three faces meet, I think of a corner of a box when I forget.
• what is a vertices
• A vertex is an intersecting point, or where two lines/sides meet. The plural form of vertex is vertices.
(1 vote)
• how do you find the area of a triangle?
(1 vote)
• There are several ways, easiest is A=1/2 bh where b is the base and h is the height, these are perpendicular to each other.
• How do I figure out how many vertices a shape has? Like what about vertices?
• Just count up the corners
(1 vote)
• Do we have to add up all the sides together?