Répondre :
√(9 x^{2}+12x+4)=3
9x²+12x+4=9 -> 9x²+12x-5=0
delta = b²-4ac = 144-(4*9*-5) = 324
x1 = -12-racine(324)/2/9 = -13
x2 = -12+racine(324)/2/9 = -11
9x²+12x+4=9 -> 9x²+12x-5=0
delta = b²-4ac = 144-(4*9*-5) = 324
x1 = -12-racine(324)/2/9 = -13
x2 = -12+racine(324)/2/9 = -11