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'Dodecawhat' printed from https://nrich.maths.org/
Why do this problem?
The stimulus for the problem is the engaging context of the
construction of the solid. Is this really a regular dodecahedron
and how can we be sure?
Possible approach
Without discussing how or why the pentagon is regular,
encourage learnersto make pentagons and put them together to make a
dodecahedron.
Then challenge them to examine whether the pentagons are
actually regular or not.
Key Questions
- How do you know this is a regular pentagon?
- What would have to be the case for the pentagon to be regular
(all sides and all angles equal)?
- What do we know?
- What mathematics do you know that might be useful?
Support
Making this and other solids in similar ways, see the
article
on constructing platonic solids. The focus for the learners is
on reading and following written instructions as much as on gaining
greater familiarity with 3D shapes.
Extension
The A4 paper part of theproblem.