Two-Dimensional Geometry
This page focuses on the fundamental calculations for two-dimensional geometric shapes, including perimeter and area formulas for basic planar figures.
Definition: A two-dimensional shape is a flat figure that has only length and width.
Vocabulary:
- Disc (Disque): A flat, circular shape
- Triangle: A polygon with three sides
- Rectangle: A quadrilateral with four right angles
- Parallelogram: A quadrilateral with opposite sides parallel
Example: For a triangle:
- Area = (base × height) ÷ 2
- Where base and height must be perpendicular to each other
Highlight: The perimeter formulas focus on the sum of all sides, while area formulas typically involve multiplication of key dimensions.



























