Week 9: Expressions & Equations

← Back to Autumn Term

Topic: Introduction to Algebra: Expressions & Equations

Introduction

Welcome to the world of algebra! This week, we learn how to use letters to represent unknown numbers. We'll start by simplifying expressions and then move on to solving equations to find the value of the unknown.

Key Concepts Covered

  • Simplifying Expressions: Collecting 'like terms' (e.g., 3a + 2a = 5a).
  • Expanding Brackets: Multiplying a term outside a bracket with everything inside (e.g., 4(x + 3) = 4x + 12).
  • Solving One-Step Equations: Finding the unknown in equations like x + 9 = 17 or 3x = 21.
  • Solving Two-Step Equations: Using the 'balance method' to solve equations like 2x + 5 = 15.
  • Substitution: Replacing a letter with a given value to find the value of an expression.

In-Class Activities

Let's make algebra interactive:

  • The Balance Method: Using a visual of scales to understand how to keep an equation balanced while solving it.
  • Equation Treasure Hunt: Solve equations to find coordinates on a grid, leading to a hidden treasure!

📝 Mini-Assessment (10 marks)

  1. Simplify: 3a + 2a − a. (1 mark)
  2. Expand: 4(x + 3). (1 mark)
  3. Simplify: 5x + 7 − 2x + 4. (2 marks)
  4. Solve: x + 9 = 17. (1 mark)
  5. Solve: 2x + 3 = 15. (2 marks)
  6. If y = 4, find the value of 3y + 5. (1 mark)
  7. A number n is doubled and then 5 is added. The result is 21. Write and solve an equation to find n. (2 marks)

📖 Homework

This week's homework is a practice worksheet on solving linear equations to reinforce the skills learned in class.