Math lesson plan · 9th grade (Year 10 in England) · 45 minutes
Solve linear equations by clearing fractions
Algebra
CCSS HSA.REI.B.3England: GCSE Foundation AlgebraEngland: GCSE Higher Algebra
Objective and success criteria
Students will: Solve linear equations by clearing fractions.
- I can answer questions on today's skill on my own, without help.
- I can explain each step and say why it works.
- I can check my answer and spot a mistake.
Before and after
Needs first: Equations with the unknown on both sides
Leads to: the next skill in this area.
Materials: Balance scales or a balance drawing, Algebra tiles, Function machine cards, Mini whiteboards and pens, Printed student sheet (below).
Warm-up · 5 min
- Quick retrieval from earlier learning (Equations with the unknown on both sides). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- Solve: 9x + 15 = 5x + 43 → x = 7Prompt: Collect the x terms on one side.
- Solve: 4(x − 4) = 5(x − 2) − 13 → x = 7Prompt: Expand the brackets on both sides first.
- How many solutions does 2x + 8 = 2x + 8 have? (No solution / Infinitely many solutions / Exactly one solution) → Infinitely many solutionsPrompt: Subtract the x terms from both sides. What is left?
Hook · 5 min
- Show a "think of a number" puzzle and ask the class to work out the starting number.
- Share the objective: Solve linear equations by clearing fractions. Read the success criteria together.
I do: model it · 10 min
- Work through the example out loud, saying why you do each step, not just what you do.
- Example: Solve: x/4 + 4 = 10
- Step 1: x/4 = 6
- Step 2: x = 6 × 4
- Step 3: x = 24
- Answer: x = 24
- Pause after each step and ask a student to say what comes next.
We do: guided practice · 10 min
- Do these together. Students try each step on whiteboards before you reveal it.
- Use the hints as prompts rather than giving the answer.
- Solve: x/5 + 3 = 1 → x = -10Prompt: First undo the + 3.
- Solve: (x − 6)/2 = −2 → x = 2Prompt: Multiply both sides by 2 to clear the fraction.
You do: independent practice · 10 min
- Students work on the student sheet. Circulate and check the first two answers of every student early.
- Students who finish: write a question of their own for a partner, with the answer.
The 8 questions are on the student sheet below, with answers in the key.
Exit ticket · 5 min
- Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.
- Solve: x/3 + x/6 = 12 → x = 24Prompt: What is the lowest common multiple of 3 and 6?
- Solve: x/7 + 3 = 5 → x = 14Prompt: First undo the + 3.
Watch out for
- Doing an operation to one side of an equation but not the other.
- Reading 3x as 3 + x, or thinking x always stands for one particular number.
Support and stretch
Support
- Review first: Equations with the unknown on both sides.
- Use concrete materials: balance scales or a balance drawing.
- Give the first step of each question, or a partly worked example to finish.
- Pair with a confident partner for the guided practice.
Stretch
- Explain a common mistake in writing and how to fix it.
- Write a word problem that uses today's skill, then solve a partner's.
Homework and more practice
Free online practice with hints and printable worksheets for this skill: eurekami.com/math/grade-9.
Free lesson plan from eurekami.com/lesson-plan-builder