4(х+3)-(0,5х+1)(2х+6)<6</p>
4x + 12 - (x^2 + 3x + 2x + 6) < 6 4x + 12 - (x^2 + 5x + 6) < 6 4x + 12 - x^2 - 5x - 6 - 6 < 0 - x^2 - x < 0 x^2 + x > 0 x (x + 1) > 0 + - + ----------- (-1) ----------- (0) -----------> x x ∈ ( - ∞; - 1) ∪ (0; + ∞)