# Lesson 14

Nets and Surface Area

Let’s use nets to find the surface area of polyhedra.

### Problem 1

Can this net be assembled into a cube? Explain how you know. Label parts of the net with letters or numbers if it helps your explanation.

### Problem 2

1. What polyhedron can be assembled from this net? Explain how you know.

2. Find the surface area of this polyhedron. Show your reasoning.

### Problem 3

Here are two nets. Mai said that both nets can be assembled into the same triangular prism. Do you agree? Explain or show your reasoning.

### Problem 4

Here are two three-dimensional figures.

Tell whether each of the following statements describes Figure A, Figure B, both, or neither.

1. This figure is a polyhedron.
2. This figure has triangular faces.
3. There are more vertices than edges in this figure.
4. This figure has rectangular faces.
5. This figure is a pyramid.
6. There is exactly one face that can be the base for this figure.
7. The base of this figure is a triangle.
8. This figure has two identical and parallel faces that can be the base.
(From Unit 1, Lesson 13.)

### Problem 5

Select all units that can be used for surface area.

A:

square meters

B:

feet

C:

centimeters

D:

cubic inches

E:

square inches

F:

square feet

(From Unit 1, Lesson 12.)

### Problem 6

Find the area of this polygon. Show your reasoning.