Algebraic fractions follow the same rules as numeric fractions — but you must factorise before you simplify.

• Simplify by factorising the numerator and denominator, then cancelling common FACTORS (never terms).
• Multiplying: factorise, cancel, then multiply straight across.
• Dividing: multiply by the reciprocal of the second fraction.
• Adding/subtracting: find the lowest common denominator (LCD) after factorising.

• LCD — the smallest expression every denominator divides into.
• Restriction — a value that makes a denominator zero and is therefore not allowed.