Subtracting 4, we get - 3 - 4 ≤ 4 - $\frac{7x}{2}$ - 4 ≤ 18 - 4 or - 7 ≤ $\frac{-7x}{2}$ ≤ 14 Multiplying each side by − $\frac{2}{7}$ , we get - 7 × $\left(-\frac{2}{7}\right)$ ≥ $\frac{-7}{2}$ x × $\left(-\frac{1}{7}\right)$ ≥ 14 × $\left(-\frac{2}{7}\right)$ 2 ≥ x ≥ – 4 or –4 ≤ x ≤ 2 ∴ x is less than or equal to 2 and greater than or equal to –4. i.e., x ∈ [– 4, 2]