Leo+DadMade for Leo
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Concept · 4 steps · NESA MA4-LEN-C-01

Perimeter of Quadrilaterals & Composite Figures

The distance all the way round a shape — easy on a plain rectangle, sneaky on an L-shape. Get the "add every side, but only the real ones" habit and the marks look after themselves.

1Where it comes fromPerimeter is just every side added up. Walk around the edge and watch it grow. 2How to do itThe rectangle shortcut — 2 × (length + width) — with a practice generator. 3Where it gets trickyL-shapes: work out the missing sides, and don't count the cut line. 4Out in the wildFencing a yard, framing a picture, and working a side out backwards.
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