Answer 1

9x – 1 ≤ 28 + 4x

⇒ 9x – 4x – 7 ≤ 28 + 4x – 4x (Subtracting 4x)

⇒ 5x – 7 ≤ 28

⇒ 5x – 7 + 7 ≤ 28 + 7 (Adding 7)

⇒ 5x ≤ 35

⇒ x ≤ 7 (Dividing by 5)

Required answer = {0, 1, 2, 3, 4, 5, 6, 7}