0}} \right.
1)x^{2} +9x+20=0; D=81-80=1; x1=(-9+1):{2} = -4 x2=(-9-1):{2} = -5; 2) x+3>0 x>-3" alt="\left \{ {{x^{2}+9x+20\leq0 } \atop {x+3>0}} \right.
1)x^{2} +9x+20=0; D=81-80=1; x1=(-9+1):{2} = -4 x2=(-9-1):{2} = -5; 2) x+3>0 x>-3" align="absmiddle" class="latex-formula">
Ответ: [-5;-4]∪(-3;+∞)