3(-3 + 7x) ≤ -93
-3 + 7x ≤ -31
7x ≤ -28
x ≤ -4
Answer: x ≤ -4
-6(1 + 8x) ≥ 138
Multiplying or dividing both sides by a negative number flips the sense of the inequality.
1 + 8x ≤ 138/(-6) = -23
8x ≤ -24
x ≤ -24/8
Answer: x ≤ -3
7(6x - 4) ≥ 6x - 28
42x - 28 ≥ 6x - 28
36x ≥ 0
x ≥ 0
Answer: x ≥ 0
86 ≤ -4(1 - 5x) - 2x
86 ≤ -4 + 20x - 2x
90 ≤ 18x
5 ≤ x
Answer: x ≥ 5
