TRI004 · Triangles · Classes 6–12
Right Triangle
A right triangle has one 90° angle. The side opposite it is the hypotenuse, the longest side.
Right Triangle📐 Formula
Pythagoras: c² = a² + b²; Area = ½ab
✏️ Worked example
Legs 3 and 4: c = √(9 + 16) = 5; area = 6.
🌍 Where it is used
Ladders against walls, ramps and finding distances on a map.
❓ Quick check
Legs 6 and 8. The hypotenuse is…