What are the unknown side lengths in similar triangles PQR and ABC?

In similar triangles PQR and ABC, the corresponding side lengths maintain a constant ratio. To find the unknown side lengths, you can set up a proportion based on the known lengths of the triangles. For example, if you know the lengths of two sides from each triangle, you can solve for the unknowns by cross-multiplying and dividing. Make sure to match corresponding sides correctly to maintain the similarity ratio.