Determine the Area of Trapezoids

6.GR.1 · Unit 5 · Lesson 3

Name   Period

Objectives / Objetivos

Content Objective: I can find the area of a trapezoid using the formula A = ½(b1 + b2) × h.

Language Objective: I can explain my steps using the words trapezoid, base, height, and area.

Key Idea / Idea clave

Area of Trapezoids. Formula: Area = ½ × (b1 + b2) × h. 1. A trapezoid is a four-sided shape with one pair of parallel bases. 2. Add the two bases together: (b1 + b2). 3. Multiply by the perpendicular height, then take half

I Notice / Observo

  • What shape is the window?
  • How many parallel sides does it have?

I Wonder / Me pregunto

  • Why does the formula use two bases instead of one?

Vocabulary / Vocabulario

Term / TérminoDefinition / Definición
Area of Trapezoids
Área de trapecios		The space inside a trapezoid. Formula: A = 1/2(b₁ + b₂)h.
El espacio dentro de un trapecio. Fórmula: A = 1/2(b₁ + b₂)h.
Trapezoid
Trapecio		A four-sided shape with just one pair of parallel sides.
Una figura de cuatro lados con solo un par de lados paralelos.
Parallel
Paralelas		Two lines or sides that stay the same distance apart and never meet.
Dos líneas o lados que se mantienen a la misma distancia y nunca se cruzan.
Base 1 (b1)
Base 1 (b1)		One of the two parallel sides of a trapezoid.
Uno de los dos lados paralelos de un trapecio.
Base 2 (b2)
Base 2 (b2)		The other parallel side of a trapezoid.
El otro lado paralelo de un trapecio.
Height
Altura		The straight-up distance between the two parallel sides.
La distancia recta entre los dos lados paralelos.

Practice Preview / Vista previa de práctica

  1. What is the area of a trapezoid with bases 6 cm and 10 cm, and height 4 cm?
    1. 32 sq cm
    2. 64 sq cm
    3. 24 sq cm
    4. 40 sq cm
  2. Problem 2
  3. Match each shape to its area.
  4. Find the Area Error
    1. Step 1: Identify the bases and height — b₁ = 10 m, b₂ = 6 m, h = 7 m
    2. Step 2: Write the formula — A = ½ × (b₁ + b₂) × h
    3. Step 3: Substitute values — A = ½ × (10 + 6) × 7
    4. Step 4: Calculate — A = (10 + 6) × 7 = 112 sq m

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

Reflection / Reflexión

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