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# Triangle similarity

5 videos
4 skills
This tutorial explains a similar (but not congruent) idea to congruency (if that last sentence made sense, you might not need this tutorial). Seriously, we'll take a rigorous look at similarity and think of some reasonable postulates for it. We'll then use these to prove some results and solve some problems. The fun must not stop!

### Similar triangle basics

VIDEO 9:17 minutes
Introduction to what it means for triangles to be similar

### Similarity postulates

VIDEO 12:14 minutes
Thinking about what we need to know to determine whether two triangles are similar

### Similar triangles 1

PRACTICE PROBLEMS

### Similar triangle example problems

VIDEO 9:23 minutes
Multiple examples looking for similarity of triangles

### Similar triangles 2

PRACTICE PROBLEMS

### Similarity example problems

VIDEO 7:37 minutes
Two example problems involving similarity

### Solving similar triangles 1

PRACTICE PROBLEMS

### Similarity example where same side plays different roles

VIDEO 6:05 minutes
The same side not corresponding to itself in two similar triangles

### Solving similar triangles 2

PRACTICE PROBLEMS