Triangle similarity: Definition, criteria and demonstrations
- Jorge Cássio
Change the positions of points A, B, C, A', B' or C'. What do you see regarding the value of k?
Change the positions of points A, B, C, A ', B' or C 'so that k is equal to 1. What can you notice about the triangles?
1st Similarity Case: ANGLE-ANGLE SIMILARITY
2nd Similarity Case: Side-Angle-Side
Find a reason for the use of theorem in the previous demonstration: "If a line divides two sides of a triangle and determines segments proportional to those two sides, then it is parallel to the third side." Use the following figure as reference.