Topic notes and worked questions
Algebra & Equations
Algebra is easier when every move preserves equality. These guides focus on legal operations, clear lines of working and quick substitution checks.
Linear equations with fractions
Clear denominators first, then solve without dropping signs.
Simultaneous equations by elimination
Scale equations strategically so one variable cancels cleanly.
Completing the square explained
Turn a quadratic into square form and see why half the x-coefficient matters.
Before you calculate
Underline what the question gives you and what it actually asks for. Many errors happen before the arithmetic starts.
After you calculate
Look at the size and sign of the answer. A ten-second sense check can catch a wrong setup.
When units appear
Keep them beside the numbers. Converting early is often safer than trying to repair units at the end.