DRAWINGS, CROSS SECTIONS AND NETSpapgeometry.weebly.com/uploads/2/2/8/6/22869852/day_1...Cross...

P R E P A R I N G F O R S U R F A C E A R E A A N D V O L U M E

DRAWINGS, CROSS SECTIONS AND NETS

ISOMETRIC DRAWINGS

A DRAWING THAT LOOKS

3 DIMENSIONAL.

FOUNDATIONAL DRAWING

A DRAWING THAT SHOWS

THE BASE OF THE STRUCTURE

AND THE HEIGHT OF EACH

PART.

ORTHOGRAPHIC PROJECTION

IS A 2D DRAWING OF THE

FRONT, TOP AND SIDE VIEWS

OF 3D OBJECT.

12.1 EXPLORE SOLIDS

• A ________ is a solid that is bounded by

polygons, called _______, that enclose a single

region of space.

• An _______ of a polyhedron is a line segment

formed by the intersection of two faces.

• A _________ of a polyhedron is a point where

three or more edges meet.

Polyhedron

faces

Edge

Vertex

TYPES OF SOLIDS:

CLASSIFYING SOLIDS

• Classifying Solids: Of the five solids on the previous

slide, the prism and pyramid are polyhedra. To name

a prism or pyramid, use the shape of the base.

PLATONIC SOLIDS

CROSS SECTIONS

Cross Section:

2D shape on the surface of the intersection

EXAMPLE 4:

Square Rectangle Trapezoid

NETS

NET: THE TWO-DIMENSIONAL REPRESENTATION OF THE

FACES OF A 3-DIMENSIONAL OBJECT.

Find the surface area using the

net.

Rectangular prism surface area:

2(6)+ 2(18) + 2(12)= 72 square units

Triangular prism surface area:

12 + 9+ 15 + 6+6= 48 square units