Lesson Plan

Lesson Plan
Grade: Date: 18/01/2026
Subject: Additional Mathematics
Lesson Topic: Use substitution to form and solve a quadratic equation in order to solve a related equation
Learning Objective/s:
  • Describe the purpose of substitution in transforming non‑standard equations into quadratic form.
  • Apply a step‑by‑step procedure to substitute, solve, and back‑substitute for the original variable.
  • Check derived solutions against the original equation to identify extraneous roots.
  • Solve a range of practice problems using substitution with confidence.
Materials Needed:
  • Projector or interactive whiteboard
  • Prepared slide showing the substitution procedure
  • Worksheet with guided example and practice questions
  • Graph paper and calculators for checking solutions
  • Sticky notes for exit tickets
Introduction:

Begin with a quick “Do‑Now” asking students to solve \(x^2-5x+6=0\) and notice the ease of factoring. Review the quadratic formula and remind learners that many complex equations hide a quadratic pattern. Explain that today they will learn a systematic substitution method and will be able to state the success criteria: correctly identify a substitution, solve the resulting quadratic, and verify solutions.

Lesson Structure:
  1. Do‑Now & discussion (5') – Students share answers to the warm‑up quadratic and identify the pattern.
  2. Mini‑lecture (10') – Present the six‑step substitution algorithm with a visual slide.
  3. Guided example (15') – Work through the provided \(\frac{1}{x}+\frac{1}{x^{2}}=6\) problem, prompting students to suggest each step.
  4. Partner practice (12') – Learners attempt the three practice equations on the worksheet, using the algorithm checklist.
  5. Check & feedback (8') – Review answers as a class, highlighting common errors and the importance of checking solutions.
  6. Exit ticket (5') – Students write one example of a substitution they could use in a new problem.
Conclusion:

Summarise the substitution cycle: identify, rewrite, form a quadratic, solve, back‑substitute, and verify. Collect exit tickets to gauge understanding and assign homework: three additional substitution problems from the textbook. Remind students that mastering this technique expands the range of equations they can tackle confidently.