Verified answer

Bonjour

M = (x - 3)^2 - 9

1) calculer M pour x = 6 :

M = (6 - 3)^2 - 9

M = 3^2 - 9

M = 9 - 9

M = 0

2) developper M :

M = x^2 - 6x + 9 - 9

M = x^2 - 6x

3) factoriser M :

M = (x - 3)^2 - 3^2

M = (x - 3 - 3)(x - 3 + 3)

M = (x - 6) * x

M = x(x - 6)

4) résoudre l’équation M = 0

x(x - 6) = 0

x = 0 ou x - 6 = 0

x = 0 ou x = 6