svp pour demain.. uurrgeent !! Niveau 3eme

Salut,

(x+5)² = 6
(x + 5)² - 6 = 0
(x+5)² - √6² = 0
(x+5 + √6)(x+5 - √6) = 0

x+5 + √6 = 0
x = -5 - √6

x+5 -  √6 = 0
x = -5  + √6

(2x + 8 )² = 0
2x + 8 = 0
2x = -8
x = -4.

(4x - 5)² = -5
=> Impossible en 3ème ...