4 – x ≥ 0 -x ≥ -4 x ≤ 4 10 = 4 – x x = 4 – 10 x = -6

4 – x ≤ 0 -x ≤ -4 x ≥ 4 10 = -(4 – x) 10 = -4 + x x = 14

x1 = -6 x2 = 14