The answer is 0 < x ≤ 7
First, we know that width = x
Which means that length = x +18
So, the possible equation for the Table's area is
X (X + 18) ≤ 175
X^2 + 18x - 175 ≤ 0
Next, we need to calculate is by using complete square method
x^2 + 18x + 81 ≤ 175 + 81
(x + 9)^2 ≤ 256
|x + 9| ≤ sqrt(256)
|x + 9| ≤ +-16
-16 ≤ x + 9 ≤ 16
-16 - 9 ≤ x ≤ 16 - 9
-25 ≤ x ≤ 7
Since the width couldn't be negative, we can change -25 with 0,
so it become
0 < x ≤ 7
