Isosceles & Equilateral Triangles
Section: GeometryBank code: GEO-IETGRE frequency: MediumPro
1. Core Idea
- Isosceles: two equal sides, and therefore two equal angles (the base angles, opposite the equal sides).
- Equilateral: all three sides equal, so all three angles are 60 degrees.
The equal-sides/equal-angles link runs both ways, and that biconditional is what most questions exploit: prove two angles equal and you have proved two sides equal.
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