Lesson 8.28.2 Small Group · Group 1
Start hereWords, worked example, and sentence starters
Learning target With my small group, I can solve one-step addition and subtraction equations using inverse operations — one step at a time, with support.
Why This Matters This is your support small group for Lesson 8.2. We're going to slow this down and build it together, one step at a time. You can ask a question any time — that's what this group is for.
Start hereWords for this lesson
Read each word before you begin. Say it out loud.
| Word | What it means | Example |
|---|---|---|
| EquationSpanish: Ecuación | A math sentence with an equal sign showing both sides are the same. | x + 25 = 60 — both sides equal 60 when x = 35 |
| Inverse operationSpanish: Operación inversa | Two math actions that undo each other, like × and ÷. | + and − |
| IsolateSpanish: Despejar | To get the letter by itself on one side. | get x by itself |
| SolutionSpanish: Solución | A number that makes the equation or inequality true. | x = 7 is the solution to x + 5 = 12 because 7 + 5 = 12 ✓ |
| One-step equationSpanish: Ecuación de un paso | An equation you can solve in a single step using one inverse operation. | x + 7 = 20 |
| BalanceSpanish: Equilibrio | Keeping both sides of an equation equal by doing the same thing to each side. | do the same to each side |
How it worksWorked example
These numbers are not on your problems. The steps are. Follow them with your own numbers.
A team had some points, then scored 14 more and has 40. Solve y + 14 = 40.
- Subtract 14 from both sides: y + 14 − 14 = 40 − 14.
- Simplify: y = 26.
- Check: 26 + 14 = 40.
Answer: y = 26 points
Now you trySame steps, your turn
The steps are the same as the worked example. The numbers are yours. Do the work.
Solve x − 4 = 9.
Say it and write itSentence starters
Finish each sentence out loud with a partner. Then use them in your writing.
- The variable has added to it, so I from both sides.
- I must do the same thing to both sides because .
- My solution is , and my check shows .
- Addition and subtraction are inverse operations because .
Word bank equationvariableinverse operationsubtractisolatebalanceboth sidessolutioncheckundoProperty of Equality
Watch out!A common mistake
A common mistake is applying the same operation instead of the inverse
Lesson 8.28.2 Small Group · Group 1
Group 1Supported practice
Learning target With my small group, I can solve one-step addition and subtraction equations using inverse operations — one step at a time, with support.
Why This Matters This is your support small group for Lesson 8.2. We're going to slow this down and build it together, one step at a time. You can ask a question any time — that's what this group is for.
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1Complete each step, then write the final answer.
Take 14 from both sides to keep it balanced. Solve n + 14 = 31.
- 1What number is added to n?
- 2Subtract 14 from both sides. What is 31 − 14?
- 3Check: put 17 in for n. What is 17 + 14?
Final answer: -
2Complete each step, then write the final answer.
Keep both sides balanced. Solve x − 8 = 15.
- 1Is 8 added to x or subtracted from x? What undoes it?
- 2Add 8 to both sides. What is x?
- 3Check: put 23 in for x. What is 23 − 8?
Final answer: -
3Complete each step, then write the final answer.
Solve x + 6 = 20.
Show your workHint 6 is added to x. Subtract 6 from both sides.
Final answer: -
4Complete each step, then write the final answer.
Solve n − 27 = 46.
Show your workHint 27 is subtracted from n. Do the inverse to both sides.
Final answer: -
5Complete each step, then write the final answer.
The old weight plus 9 pounds is 26 pounds. A puppy gained 9 pounds this year. Now it weighs 26 pounds. Write and solve an equation. How much did it weigh before?
Show your workHint Let w be the weight before. Write w + 9 = 26. Undo the + 9.
Final answer: -
6Complete each step, then write the final answer.
Kai solved x − 12 = 30 and got x = 18. Is he right? What is x?
Show your workHint Check Kai's answer first: what is 18 − 12? Then think about which operation undoes − 12.
Final answer:
Explain your thinkingKai subtracted when he should have added. How do you know which inverse operation to use?
Sentence starter The equation ___ the number, so I ___ to undo it. · I check my answer by ___.