Bonjour ,
1/
5^2 - (x+1)^2 = 0
[5-(x+1)] [5+(x+1)] = 0
(4-x) (6+x) = 0
4-x = 0 6+x = 0
x = 4 ou x = -6 .
2/
[(2x-3)-(5x+1)] [(2x-3)+(5x+1)] = 0
[2x-3-5x-1] [2x-3+5x+1] =0
(-3x-4) (7x-2) = 0
-3x-4=0 ou 7x-2=0
-3x=4 7x=2
x=4/-3. x=2/7 .
** Je te laisse faire la dernière !! ;)