besoin d'aide pour la question 4 a et b et la 5 merci.

g(x) =(x-1)(x+3)
= x²+3x-x-3
=x²+2x-3

g(x) =(x+1)(x+3)

x+1 =0                           x+3 =0
x = -1                            x = -3



x²+2x-3 = -3
x²+2x = -3+3
x²+2x =0
x(x+2) =0

x=0                      et  x+2 = 0
                                  x =  -2