Answer:
the smallest number is the lower bound and the largest number is the upper bound, your inequality would be
8.2 ≤ x ≤ 9.5, where x represents the volume of tennis balls.
The surface area is 253.5 but Im not sure
6x + 18y = 18. Let us take x = 0
6(0) + 18y = 18
0 + 18y = 18
18y = 18
y = 18/18
y = 1
(0, 1) [x = 0, y = 1]
6x + 18y = 18. Let us take y = 0
6x + 18(0) = 18
6x + 0 = 18
6x = 18
x = 18/6
x = 3
(3, 0) [x = 3, y =0]
Infinite solutions can be found for x and y