Write and Evaluate Algebraic Expressions

6.AT.6a · Unit 6 · Lesson 5

Name   Period

Objectives / Objetivos

Content Objective: I can write an algebraic expression for a real situation and evaluate it for a given value of the variable.

Language Objective: I can explain my expression using the words variable, term, coefficient, constant, substitute, and evaluate.

Key Idea / Idea clave

Writing & Evaluating Algebraic Expressions. 1. Define the variable to represent the unknown quantity. 2. Translate mathematical phrases into operations, coefficients, and constants. 3. Evaluate by substituting given numerical values for the variable

I Notice / Observo

  • What value changes depending on how many people come?
  • What stays the same no matter the number of tickets?

I Wonder / Me pregunto

  • What if there were two different ticket prices — regular and VIP?

Vocabulary / Vocabulario

Term / TérminoDefinition / Definición
Write Algebraic Expressions
Escribir expresiones algebraicas		Translate words or a situation into numbers, variables, and operation symbols.
Traducir palabras o una situación a números, variables y símbolos de operaciones.
Variable
Variable		A letter that stands for a number that is unknown or can change.
Una letra que representa un número desconocido o que puede cambiar.
Algebraic Expression
Expresión algebraica		A math phrase that has at least one letter.
Una frase matemática que tiene al menos una letra.
Coefficient
Coeficiente		The number in front of a letter, like the 3 in 3x.
El número frente a una letra, como el 3 en 3x.
Constant
Constante		A fixed number in an expression or equation that does not change.
Un número fijo en una expresión o ecuación que no cambia.
Like terms
Términos semejantes		Terms with the same letter raised to the same power, like 2x and 5x.
Términos con la misma letra elevada a la misma potencia, como 2x y 5x.

Practice Preview / Vista previa de práctica

  1. Which expression represents 'the product of 6 and a number n'?
    1. 6n
    2. 6 + n
    3. n − 6
    4. n ÷ 6
  2. Match each word phrase to its correct algebraic expression.
  3. Match each word phrase to its algebraic expression.
  4. Find the Translation Error
    1. Step 1: Phrase — 12 less than a number g
    2. Step 2: Student's expression — 12 − g
    3. Step 3: Reasoning — I see 'less than' so I subtract, and 12 comes first in the phrase.

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

Reflection / Reflexión

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