Răspuns:
x ∈ [-5 ; 0]
Explicație pas cu pas:
x² + 5x ≤ 0
7 + x > 0 <=>
x·(x+5) ≤ 0
x > -7
x I -∞ -7 -5 0 +∞
x I----------------------------- 0 +++++++++++
x+5 I----------------------- 0 +++++++++++++++
x·(x+5) I+++++++++++++++0 --- 0 ++++++++++
x+7 I---------------- 0 +++++++++++++++++++ =>
x ∈ [-5 ; 0] ∩ (-7 , +∞) =>
x ∈ [-5 ; 0]