Neft Teacher · Notes Packet

Unit 7 · Standard 6.EE.7

Solve One-Step Addition and Subtraction Equations

Lesson 7-2

Name:Date:Class:

Key Vocabulary Level 1 support

Picture first, then the word, then a plain-language meaning. Say each word out loud.

Illustration of Equation: A math sentence with an equal sign showing both sides are the same.

x + 5 = 12 — both sides equal 12 when x = 7

Equation

A math sentence with an equal sign showing both sides are the same.

Illustration of Inverse operation: Two math actions that undo each other, like × and ÷.

Addition undoes subtraction: if x − 3 = 10, add 3 to get x = 13

Inverse operation

Two math actions that undo each other, like × and ÷.

Illustration of Isolate: To get the letter by itself on one side.

x + 5 = 12 → subtract 5 from both sides → x = 7 (x is isolated)

Isolate

To get the letter by itself on one side.

Illustration of Solution: The number that makes the equation true.

x = 7 is the solution to x + 5 = 12 because 7 + 5 = 12 ✓

Solution

The number that makes the equation true.

Key Ideas & Notes

Think About It

  • What operation connects the locker number and 23?
  • What does n represent in the equation?
  • How could you undo the addition to find n?

My Notes

Guided Examples

Example 1

Solve: x + 9 = 15

Solution: Subtract 9 from both sides: x = 15 − 9 = 6. Check: 6 + 9 = 15 ✓

Answer: A. x = 6

Example 2

Solve: y − 7 = 20

Solution: Add 7 to both sides: y = 20 + 7 = 27. Check: 27 − 7 = 20 ✓

Answer: A. y = 27

Example 3

Solve: n + 15 = 42

Solution: Subtract 15 from both sides: n = 42 − 15 = 27. Check: 27 + 15 = 42 ✓

Answer: A. n = 27

Write About the Math The Writing Revolution

I can explain my steps using the words equation, inverse operation, isolate, and solution.

1. Kernel Sentence subject + verb

Model: Equation is a math sentence with an equal sign showing both sides are the same.Ecuación es una oración matemática con un signo igual que muestra que ambos lados son iguales.

Write a kernel sentence about equation. Use a subject and a verb.Escribe una oración base sobre ecuación. Usa un sujeto y un verbo.

2. Sentence Expansion because · but · so

Kernel: Equation matters in mathEcuación importa en matemáticas

Expand the kernel three ways. Add a reason, a contrast, and a result.

becauseporque

Equation matters in math because ___.Ecuación importa en matemáticas porque ___.

butpero

Equation matters in math, but ___.Ecuación importa en matemáticas, pero ___.

soentonces

Equation matters in math, so ___.Ecuación importa en matemáticas, entonces ___.

3. Sentence Types 4 ways to write a math idea

StatementAfirmación

Tell one true fact about equation.Di un hecho verdadero sobre equation.

Equation ___.

QuestionPregunta

Ask a question about equation.Haz una pregunta sobre equation.

How does ___ ?¿Cómo ___ ?

ExclamationExclamación

Show excitement about equation.Muestra entusiasmo sobre equation.

Wow, ___ !¡Guau, ___ !

CommandMandato

Tell a partner what to do with equation.Dile a un compañero qué hacer con equation.

First, ___ .Primero, ___ .

4. Explain Your Reasoning use a sentence starter

I used ___ to undo ___.Usé ___ para deshacer ___.

So the variable equals ___.Entonces la variable es igual a ___.

This helps me find ___.Esto me ayuda a hallar ___.

Try It

Solve on your own. Check the answer key when you are done.

1. Solve: m − 11 = 25

  1. m = 36
  2. m = 14
  3. m = 25
  4. m = 275
Show your work:

2. A shirt costs $d. After a $15 discount, it costs $38. What is d?

  1. $53
  2. $23
  3. $38
  4. $45
Show your work:

Stretch Your Thinking Level 2 enrichment

Challenge task — explain your reasoning in full sentences.

A detective solved x + 25 = 60 and got x = 35. Another detective solved y − 25 = 60 and got y = 35. Are both correct? Explain using inverse operations and check each answer.

Sentence starter: For x + 25 = 60, the inverse operation is ___, so x = ___. Check: ___. For y − 25 = 60, the inverse operation is ___, so y = ___. Check: ___. Therefore, ___.

Show your work:

Reflect — Exit Ticket

Solve: p + 2.8 = 9.1

  1. p = 6.3
  2. p = 11.9
  3. p = 6.8
  4. p = 3.25
Your answer:

Answer Key & Teacher Guide

  1. Try It 1: A. m = 36 — Add 11 to both sides: m = 25 + 11 = 36. Check: 36 − 11 = 25 ✓
  2. Try It 2: A. $53 — d − 15 = 38 → d = 38 + 15 = 53.
  3. Exit Ticket: A. p = 6.3 — Subtract 2.8 from both sides: p = 9.1 − 2.8 = 6.3. Check: 6.3 + 2.8 = 9.1 ✓

Writing (TWR) — what to look for