Concept · 4 steps · NESA MA4-PYT-C-01

Identifying and Defining Pythagoras' Theorem

One of the oldest, neatest facts in maths: in any right-angled triangle, the squares on the two short sides add up to the square on the longest. Get what it says first — using it to find lengths comes next.

1Where it comes fromDraw a square on every side. The two small ones always add to the big one: a² + b² = c². 2How to do itName the parts — the hypotenuse and the two legs — and state the theorem cleanly. 3Where it gets trickyThe hypotenuse isn't "the bottom", and it only works for right-angled triangles. 4Out in the wildSpotting the hidden right triangle in ladders, screens and ramps — and why c is longest.

← This concept rests on

Square Roots
Area of a Square

→ It unlocks

Applying Pythagoras' Theorem