In this Grade 8 Saxon Math Course 3 investigation, students learn to identify and classify geometric solids — including polyhedra, prisms, pyramids, cylinders, cones, and spheres — using key vocabulary such as face, edge, vertex, and apex. Students also practice representing three-dimensional figures on a two-dimensional surface using parallel projection to sketch prisms, cylinders, pyramids, and cones with accurate hidden edges shown as dashed lines.
Section 1
📘 Drawing Geometric Solids
Geometric solids are three-dimensional figures, also called space figures, because they occupy space. Key features include faces, edges, and vertices.
The terms face, edge, and vertex (pl. vertices) refer to specific features of solids.
Section 2
3D Solids: Polyhedra vs. Non-Polyhedra
Geometric solids are 3D figures that have length, width, and depth.
Think of it this way: a drawing on paper is flat, but a book is a 3D solid you can actually hold. If a 3D shape is completely blocky and flat on every side, it is a polyhedron. If it can roll smoothly on the floor (like a soup can or a party hat), it has curves and is a non-polyhedron!
Section 3
Face, Edge, and Vertex
The face of a polyhedron is one of its flat polygon surfaces. Two faces meet to form an edge, and the corners where edges intersect are called vertices.
Imagine you're holding a cardboard box. The flat sides you can touch are its faces. The sharp lines where two sides fold together are the edges. And the pointy corners where three edges meet? Those are the vertices! These three terms are the basic building blocks for describing almost any polyhedron, from a simple cube to a complex pyramid.
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Section 1
📘 Drawing Geometric Solids
Geometric solids are three-dimensional figures, also called space figures, because they occupy space. Key features include faces, edges, and vertices.
The terms face, edge, and vertex (pl. vertices) refer to specific features of solids.
Section 2
3D Solids: Polyhedra vs. Non-Polyhedra
Geometric solids are 3D figures that have length, width, and depth.
Think of it this way: a drawing on paper is flat, but a book is a 3D solid you can actually hold. If a 3D shape is completely blocky and flat on every side, it is a polyhedron. If it can roll smoothly on the floor (like a soup can or a party hat), it has curves and is a non-polyhedron!
Section 3
Face, Edge, and Vertex
The face of a polyhedron is one of its flat polygon surfaces. Two faces meet to form an edge, and the corners where edges intersect are called vertices.
Imagine you're holding a cardboard box. The flat sides you can touch are its faces. The sharp lines where two sides fold together are the edges. And the pointy corners where three edges meet? Those are the vertices! These three terms are the basic building blocks for describing almost any polyhedron, from a simple cube to a complex pyramid.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter