The domain is the acceptable values of x in the function. In this case, x = t, the number of tiles. If you think about it, the minimum number of tiles is 0 (you can't have a negative number of tiles), and the maximum number of tiles is 44 (you only have 44 tiles). So, the domain for this function is from 0 to 44.
0 to 44 written in interval notation is [0,44].
The range is the acceptable values of y in the function. In this case, y = A, the area given. A(t) = 9t, so you can use the acceptable values of t to get the range. Again, the minimum area is 0 because you can't have negative area. To find the maximum area, plug in the maximum number of tiles: 9.
A(t) = 9t
A = 9(44)
A = 396
With the maximum number of tiles, 44, the area you get is 396 cm². Therefore, the acceptable values of A are from 0 to 396.
0 to 396 written in interval notation is [0, 396].