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Triangle Forge

Clip sticks and fan-angles onto a floppy frame — feel which trios lock.

Both triangles are floppy — drag corners, then add pieces

YOUR FORGETHE TWIN — same piecesABCA′B′C′

the kit — drag a piece onto the left triangle · or tap-then-tap · max 3

forge collection · 0/7

how it works

Place pieces on your forge — the twin copies them. Tune any value: if the rule holds, OVERLAY always matches. Move a twin piece to a different spot, or wiggle SSA / resize AAA — same pieces, different triangle.

For the teacher

Students reach the congruence rules by building — not by being told.

YESTEM — Say yes to STEM