Lesson 8.3Division Equations
Start hereWords, worked example, and sentence starters
Learning target I can solve one-step multiplication and division equations using inverse operations.
Start hereWords for this lesson
Read each word before you begin. Say it out loud.
| Word | What it means | Example |
|---|---|---|
| Inverse operationSpanish: Operación inversa | Two math actions that undo each other, like × and ÷. | ÷ and × |
| MultiplySpanish: Multiplicar | To add equal groups again and again. | 3 × 7 = 21 means 3 groups of 7 equals 21 |
| DivideSpanish: Dividir | To split into equal groups. | 36 ÷ 4 = 9 means 36 split into 4 equal groups gives 9 per group |
| IsolateSpanish: Despejar | To get the letter by itself on one side. | 3x = 21 → divide both sides by 3 → x = 7 (x is alone) |
| CoefficientSpanish: Coeficiente | The number in front of a letter, like the 3 in 3x. | In 6x = 18, the coefficient is 6; divide both sides by 6 to get x = 3. |
| SolutionSpanish: Solución | A number that makes the equation or inequality true. | n = 32 checks out |
How it worksWorked examplesolving a division equation
These numbers are not on your problems. The steps are. Follow them with your own numbers.
A club splits a box of n pens evenly among 6 members. Each member gets 13 pens. Solve n ÷ 6 = 13.
- The variable n is divided by 6, so the inverse operation is multiplication.
- Multiply BOTH sides by 6 so the equation stays balanced.
- Left side: n ÷ 6 × 6 leaves n. Right side: 13 × 6 gives 78.
- Check: 78 ÷ 6 gives 13, so the value makes both sides equal.
Answer: n = 78, so the box held 78 pens.
Now you trySame steps, your turn
The steps are the same as the worked example. The numbers are yours. Do the work.
A baker splits k cookies evenly onto 8 trays, with 11 cookies per tray. Solve k ÷ 8 = 11.
- The variable k is divided by , so the inverse operation is .
- Multiply both sides by .
- Left side leaves . Right side: 11 × 8 = .
- Check: ÷ 8 = . Does it balance?
Say it and write itSentence starters
Finish each sentence out loud with a partner. Then use them in your writing.
- The variable is divided by , so I both sides by it.
- My equation is because the total was split into .
- The solution means in this problem.
- I checked my answer by dividing by .
Word bank equationdivisordividemultiplyinverse operationisolateboth sidesequal groupstotalsolutioncheckbalance
Watch outA common mistake
A common mistake in Solve Multiplication and Division Equations is applying the SAME operation again instead of the inverse — for example, seeing 6x = 42 and multiplying both sides by 6 to get x = 252, instead of dividing by 6 to get x = 7. Before you submit, ask: did I use the OPPOSITE operation shown in the equation, and did I apply it to both sides?
Lesson 8.3Division Equations
Apply Day · Version ASupported practice
Learning target I can solve one-step multiplication and division equations using inverse operations.
-
1Complete each step, then write the final answer.
Solve 2x = 18.
Show your workHint 2x means 2 times x. Divide both sides by 2.
Final answer: -
2Complete each step, then write the final answer.
Solve x ÷ 3 = 5.
Show your workHint x is divided by 3. Multiply both sides by 3.
Final answer: -
3Complete each step, then write the final answer.
Solve 6x = 24.
Show your workHint 6x means 6 times x. Divide both sides by 6.
Final answer:
Lesson 8.3Division Equations
Apply Day · Version BCore practice
Learning target I can solve one-step multiplication and division equations using inverse operations.
-
1Complete each step, then write the final answer.
Lia solved 3x = 45 and got x = 135. Is she right? What is x?
Show your workFinal answer: -
2Complete each step, then write the final answer.
Solve 12x = 3.
Show your workFinal answer: -
3Complete each step, then write the final answer.
Solve 7x = 56.
Show your workFinal answer:
Lesson 8.3Division Equations
Apply Day · ChallengeExtension
Learning target I can solve one-step multiplication and division equations using inverse operations.
-
1Circle the letter of the best answer. Show how you know.
What is the solution of 6m = 54?
- Am = 9
- Bm = 48
- Cm = 60
- Dm = 324
Show your work -
2Complete each step, then write the final answer.
A ribbon is cut into 6 equal pieces. Each piece is 2.5 feet long. Dev writes 6r = 2.5 for the ribbon's length r. Write the right equation. How long is the ribbon?
Show your workFinal answer: -
3Complete each step, then write the final answer.
Solve 0.25x = 7.
Show your workFinal answer: