GCSE Maths Substitution and Formulae: lesson and practice questions

By the end of this chapter you will be able to

• Use the words expression, equation, formula, identity, term and subject correctly
• Write expressions and formulae from words and from diagrams
• Substitute positive and negative numbers into expressions, working in the correct order (BIDMAS)
• Use scientific and geometric formulae such as speed, density, force, kinetic energy, area and volume
• Change the subject of a formula using inverse operations (one step, two steps, brackets, fractions, squares and roots)

You should already know

• Negative numbers and BIDMAS (Chapter 1)
• Squares, cubes and square roots (Chapter 2)
• Fractions (Chapter 3)
• Collecting like terms and algebra notation (Chapter 7)

Where this leads

• Solving linear equations (Chapter 9)
• Straight-line graphs, y = mx + c (Chapter 12)
• Speed, density and other compound measures (Chapter 16)
• Areas and volumes (Chapters 18 and 19)