Aimed at (re-)opening understanding of triangles before (re-)entering consideration of their area, this slide deck provides:

* 4 Q&A Penary slides
* 4 Worksheet slides (printable as four-sided pamphlet)
* Consideration of different types of triangle (scalene, right-angled, isosceles) in the same rectangle
* An insight into proof (if used properly)
* A trailed means to identify and distinguish the perpendicular height

Ideal for extension at Key Stage 2, focus in Key Stage 3 and support/reinforcement in Key Stage 4 / resit.

Pupil-trialled and tested .