Opposite pairs and the sine rule
Opposite pairs and the sine rule
The sine rule is for non-right-angled triangles, so you do not need a 90∘90^\circ90∘ angle. The key skill is spotting opposite pairs: an angle and the side directly across from it.
Step-by-step lessons on Edexcel IGCSE Maths The Sine Rule. Each one builds up to exam-style questions. Build confidence with the shared Foundation-tier content first, since roughly 40% of Higher-tier marks are targeted at the grades 4–5 boundary that both tiers have in common.