Pearson Geometry Common Core, 2011
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Pearson Geometry Common Core, 2011 View details
1. Space Figures and Cross Sections
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Exercise 17 Page 692

A net is a pattern made when the surface of a 3-D figure is laid out flat, showing each face of the figure. A solid may have different nets.

Verification of Euler's Formula for the Polyhedron: 7+7=12+2
Net:

Verification of Euler's Formula for the Net: 7+12=18+1

Practice makes perfect

We will verify Euler's Formula for the given polyhedron. Then, we will draw the corresponding net and verify Euler's Formula for the 2-D shape.

Verifying Euler's Formula for the Polyhedron

Let's consider the given 3-D figure.

We can see that this polyhedron has 7 faces, 7 vertices, and 12 edges. Euler's Formula states that the sum of the number of faces F and vertices V of a polyhedron is two more than the number of its edges E. Let's verify this!
F+V=E+2
7+ 7? = 12+2
14=14 âś“

Drawing the Net

A net is a pattern made when the surface of a 3-D figure is laid out flat showing each face of the figure. A solid may have different nets. The variables F, V, and E are used for different elements in 3-D and 2-D shapes.

Variable In 3-D In 2-D
F Faces Regions
V Vertices Vertices
E Edges Segments

Let's draw a net for the given figure.

Verifying Euler's Formula for the Net

In two dimensions, Euler's Formula states that the sum of the number of regions F and vertices V is one more than the number of segments E. The net we drew has 7 regions, 12 vertices, and 18 segments. Let's verify Euler's formula for our net!
F+V=E+1
7+ 12? = 18+1
19=19 âś“