Author note — to cover

a squared plus b squared equals c squared with c always opposite the right angle — G20 lists the formula among those to know — finding hypotenuses in 2D, answers as surds or rounded decimals, units consistent first. Shorter sides, coordinate distances, the converse and 3D each have sibling pages. Both tiers. (G20)

• Fluency — direct questions on pythagoras’ theorem, limited to this lesson's stated scope (4 questions).
• Application — use the same skill in unfamiliar or contextual questions without introducing a later method (4 questions).
• Check — questions built around the exclusions and likely misconceptions named in the lesson brief (4 questions).