Surface Area of Prisms

6.GR.4 · Unit 10 · Lesson 4

Name   Period

Objectives / Objetivos

Content Objective: I can find the surface area of rectangular and triangular prisms.

Language Objective: I can explain my work using the words surface area, rectangular prism, triangular prism, and face.

Key Idea / Idea clave

No matter the prism, find the area of every face and add them all together.

I Notice / Observo

  • How many faces does a rectangular prism have? A triangular prism?
  • What shapes make up the faces of a triangular prism?

I Wonder / Me pregunto

  • Which shape uses more paint — a rectangular or triangular prism of similar size?

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.
Rectangular prism
Prisma rectangular		A solid box shape with six flat rectangle sides.
Una figura sólida en forma de caja con seis lados rectangulares.
Triangular prism
Prisma triangular		A solid with two triangle ends and three flat rectangle sides.
Un sólido con dos extremos triangulares y tres lados rectangulares.
Face
Cara		One flat side of a solid shape.
Un lado plano de una figura sólida.
Net
Plantilla (desarrollo plano)		A flat shape that folds up into a solid.
Una figura plana que se dobla y forma un sólido.
Lateral face
Cara lateral		The side faces of a solid, not the top or bottom.
Los lados de un sólido, no la parte de arriba ni la de abajo.

Practice Preview / Vista previa de práctica

  1. What is the surface area of a rectangular prism with l = 5 cm, w = 4 cm, h = 3 cm?
    1. 94 cm²
    2. 60 cm²
    3. 94 cm³
    4. 47 cm²
  2. Calculate the surface area of each rectangular prism time capsule.
  3. A triangular prism has triangular bases with base 6 in and height 4 in. The prism is 10 in long and the two slant sides of the triangle are each 5 in. What is the surface area?
    1. 184 in²
    2. 160 in²
    3. 124 in²
    4. 184 in³
  4. Find the Surface Area Error
    1. Step 1: Dimensions — Rectangular prism: l = 12 cm, w = 7 cm, h = 5 cm
    2. Step 2: Formula — SA = 2lw + 2lh + 2wh
    3. Step 3: Calculate — SA = 2(12×7) + 2(12×5) + 2(7×5) = 168 + 120 + 35 = 323 cm²
    4. Step 4: Answer — Surface Area = 323 cm²

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

Reflection / Reflexión

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