Answer:
11
Step-by-step explanation:
Luke has a square patio, which means each side must have the same amount of tiles.
For example, he could have a 4 by 4 patio, 5 by 5, etc.
121 happens to be the square of 11. In other words, 11*11=121!
So, Luke can fit 11 tiles along each side of his patio.
