# Angles in triangles (age 11+)

Derive and apply formulae for the area of triangles, parallelograms, and trapezia, and for the volume of cuboids and other prisms (including cylinders), connecting each formula to its geometric reasoning

Builds on: Estimating answers (age 9+) (hard, https://ai.page/c/estimating-answers-age-9/en.md), Area of Triangles & Parallelograms (hard, https://ai.page/c/area-of-triangles-and-parallelograms/en.md), Estimating answers (age 10+) (hard, https://ai.page/c/estimating-answers-age-10/en.md)

Concept id: angles-in-triangles-age-11. Subject: maths. Licence: CC BY-SA 4.0.

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