Answer:
The AA similarity postulate???
You can use greatest common factor(gcf)
list the factors of 18 and 30.
18- 1, 2, 3, 6, 9, 18
30- 1, 2, 3, 5, 6, 10, 15, 30
now the factor that is greatest is 6.
this mean you can use the largest square tile of 6in by 6in without overlap or cutting.
Answer:
The second one I believe!