Generate Equivalent Expressions

6.AT.7 · Unit 6 · Lesson 8

Name   Period

Objectives / Objetivos

Content Objective: I can use the commutative, associative, and identity properties to rewrite expressions.

Language Objective: I can explain my reasoning using the words commutative property, associative property, and identity property.

Key Idea / Idea clave

Properties of Operations. Formula: Commutative: a + b = b + a | Associative: (a + b) + c = a + (b + c). 1. Commutative Property: Order does not change sum or product. 2. Associative Property: Grouping does not change sum or product. 3. Identity Property: a + 0 = a; a · 1 = a

I Notice / Observo

  • Does the order you add the musicians change the total?
  • What if you group different sections together first — does the total change?

I Wonder / Me pregunto

  • Do these same rules work for subtraction or division?

Vocabulary / Vocabulario

Term / TérminoDefinition / Definición
Properties of Operations
Propiedades de las operaciones
Rules that let you reorder or regroup numbers without changing an expression's value.
Reglas que permiten reordenar o reagrupar números sin cambiar el valor de una expresión.
Commutative Property
Propiedad conmutativa
You can change the order and get the same answer.
Puedes cambiar el orden y obtener la misma respuesta.
Associative Property
Propiedad asociativa
You can change the grouping and get the same answer.
Puedes cambiar la agrupación y obtener la misma respuesta.
Identity Property
Propiedad de identidad
Adding 0 or multiplying by 1 keeps the same value.
Sumar 0 o multiplicar por 1 mantiene el mismo valor.
Property
Propiedad
A rule that is always true in math.
Una regla que siempre es verdadera en matemáticas.
Distributive Property
Propiedad distributiva
Multiplying a number by everything inside the parentheses: a(b + c) = ab + ac.
Multiplicar un número por todo lo que está dentro del paréntesis: a(b + c) = ab + ac.

Practice Preview / Vista previa de práctica

Read each task. Show your work in the spaces provided and explain how you know.

1. Which property is shown? 5 + 13 = 13 + 5

  1. A Commutative Property
  2. B Associative Property
  3. C Identity Property
  4. D Distributive Property

Answer:

2. Match each equation with the property it demonstrates.

Write each item in its correct group.

Word bank: c × d = d × c (a × b) × c = a × (b × c) a + b = b + a (m + n) + p = m + (n + p) y + 0 = y x × 1 = x
Commutative
Associative
Identity

3. Match each equation to its property.

Write the letter of the matching item in the blank.

1.7 + 9 = 9 + 7A.Associative (Mult)
2.(2 × 5) × 3 = 2 × (5 × 3)B.Commutative (Mult)
3.15 × 1 = 15C.Identity (Add)
4.0 + 23 = 23D.Commutative (Add)
5.6 × 4 = 4 × 6E.Identity (Mult)
6.(8 + 3) + 7 = 8 + (3 + 7)F.Associative (Add)

4. Find the Property Error

Which step has the mistake, and what should it be?

Reflection / Reflexión

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