In a similar figure, whether the shape is a triangle, a rectangle, or a circle, these rules apply.
1. The sides do not have to be the same size or length.
2. The angles DO have to be the same measure.
3. You should be able to put one shape over the other, and expand or shrink the shape to make them exactly identical.
4. This is NOT the same as congruent. Congruent means the two shapes are exactly the same.
5. The sides should have the same ratio. For instance, a rectangle with sides labeled 40 cm and 50 cm is similar to a rectangle with side lengths 2 cm and 2.5 cm.
The ratios are: 40 and 50 = 4:5 2 and 2.5 = 4:5
Therefore, the rectangles are congruent.
