Théorème de Thalès Configuration
The Théorème de Thalès formule is presented in its basic configuration. In a triangle ABC with a line MN parallel to BC, the theorem states that AM/AB = AN/AC = MN/BC orAB/AM=AC/AN=BC/MN.
Definition: The Thales' theorem establishes a relationship between the ratios of line segments in a triangle when a line is drawn parallel to one of its sides.
An example is provided to illustrate the application of the theorem:
Example: Given AB = 45cm, AN = 20cm, BC = 27cm, AM = 25cm, and MN parallel to BC, the lengths AC and MN are calculated using the Thales' theorem.
The solution process is detailed, demonstrating how to use the theorem to find unknown lengths:
- To calculate AC: 20/AC = 25/45, resulting in AC = 36cm
- To calculate MN: MN/27 = 25/45, resulting in MN = 15cm
Highlight: The "butterfly" configuration is mentioned as a special case of Thales' theorem application.
This page provides a comprehensive introduction to the Théorème de Thalès formule 3ème, making it an excellent resource for students preparing for their brevet exams.