📐 Geometry PRO
A full geometry track with 16 phases, practice exams, and a 3D triangle constructor.
Common Core 6.G.A.1Common Core 7.G.A.2Common Core 8.G.A.1
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How it works
Worked example
The triangle constructor lets you try building a triangle with sides 2, 3, and 10 — and shows why it fails (2 + 3 is less than 10, so the sides can't meet).
Frequently asked questions
What does the 3D triangle constructor actually do?
It lets you set three side lengths and see whether they can form a real triangle — a hands-on way to learn the triangle inequality theorem.
Do I need Algebra PRO first?
No, Geometry PRO is a separate track and can be done independently.
Is there a certificate at the end?
Yes, completing all 16 phases unlocks a certificate.
For teachers and parents
Standard: Geometry (Common Core, Grades 6-8) (6.G.A.1, 7.G.A.2, 8.G.A.1).
In the classroom: Use the 3D triangle constructor as a live demo before assigning the phases — seeing an "impossible" triangle fail to close makes the rule concrete.
At home: Encourage experimenting with the triangle constructor freely, not just for the assigned exercise — trying to "break" a triangle is part of learning the rule.
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