Surface Area Using Nets

6.GR.4 · Unit 10 · Lesson 3

Name   Period

Objectives / Objetivos

Content Objective: I can find the surface area of a solid by using its net.

Language Objective: I can explain my work using the words surface area, net, face, and two-dimensional.

Key Idea / Idea clave

A box has 3 pairs of matching faces, so add up all 6 faces to get the surface area.

I Notice / Observo

  • How many faces does a rectangular prism have?
  • What shapes do you see when the box is unfolded?

I Wonder / Me pregunto

  • Is there more than one way to unfold a box into a net?

Vocabulary / Vocabulario

Term / TérminoDefinition / Definición
Surface area
Área de superficie		The total area of all the flat sides of a solid.
El área total de todos los lados planos de un sólido.
Net
Plantilla (desarrollo plano)		A flat shape that folds up into a solid.
Una figura plana que se dobla y forma un sólido.
Face
Cara		One flat side of a solid shape.
Un lado plano de una figura sólida.
Two-dimensional
Bidimensional		A flat shape with length and width, but no thickness.
Una figura plana con largo y ancho, pero sin grosor.
Edge
Arista		The line where two flat sides of a solid meet.
La línea donde se unen dos lados planos de un sólido.

Practice Preview / Vista previa de práctica

  1. A rectangular prism has l = 6 in, w = 4 in, h = 2 in. What is its surface area?
    1. 88 in²
    2. 48 in²
    3. 88 in³
    4. 44 in²
  2. Find the surface area of each time capsule box using its net.
  3. A cube has edges of 5 cm. What is its surface area?
    1. 150 cm²
    2. 125 cm²
    3. 150 cm³
    4. 30 cm²
  4. Find the Surface Area Error
    1. Step 1: Dimensions — l = 10 in, w = 4 in, h = 3 in
    2. Step 2: Formula — SA = 2lw + 2lh + 2wh
    3. Step 3: Calculate — SA = 2(10×4) + 2(10×3) + (4×3) = 80 + 60 + 12 = 152 in²
    4. Step 4: Answer — Surface Area = 152 in²

    Which step has the mistake? Explain it and write the correct work.

Reflection / Reflexión

One thing I learned today / Una cosa que aprendí hoy: