Standard practice
Equivalent pairs lie on a ray through the origin.
Amina uses 2 blue tiles for every 5 yellow tiles at the mural wall. The same relationship has to hold for a larger amount.
Equivalent ratios of the form (first part, second part) lie on a straight ray through the origin. The point (2a, 2b) belongs. A nearby point such as (2a, 2b − 1) does not, even if it looks close, because it is not the same factor on both coordinates.
Problem 1 of 9. Activate, study a model, try guided items, work independently, apply, and reflect.