Solve −15 < ^{3(x − 2)}/₅ ≤ 0

 

Multiply through by 5 (positive number, so inequality signs remain same):

−75 < 3(x − 2) ≤ 0

Divide by 3:

−25 < x − 2 ≤ 0

Add 2 to all sides:

−23 < x ≤ 2

∴ The solution is x ∈ (−23, 2]