You can tell if two shapes are similar just by looking at how they've changed, without needing to compare their sizes. There are two main types of changes (or transformations) you can use:

1. Transformations that Keep the Shape the Same:

   • Rotations: This is when you turn the shape around a point. The angles stay the same, and so does the shape.
   • Reflections: This is like making a mirror image of the shape. The size and shape stay the same, but they flip over.
   • Translations: This just means moving the shape from one place to another without changing its size or shape.

2. Dilations:

   • This type of change makes the shape bigger or smaller but keeps the same overall look. You can tell the shapes are similar if the angles that match stay the same.

Statistics show that shapes are similar when:

• All the matching angles are equal (meaning they match perfectly).
• The ratio (or the relationship) of the matching side lengths is constant.

So, you can use these transformations to see if shapes are similar, especially by looking at their angles.