Answer:
w ≥ 11.25
Step-by-step explanation:
Remember: at most, is no more than, or is less than or equal to mean to use the ≤ inequality.
length = 9 + w
width = w
P = 2l + 2w
63 ≤ 2(9 + w) + 2w
63 ≤ 18 + 2w + 2w
63 ≤ 18 + 4w
45 ≤ 4w
45/4 ≤w
11.25 ≤ w or w ≥11.25