Question

(3x +2) totul la a doua = 9

Answer 1

(3x+2)²=(-3)² sau (+3)²
1)3x+2=3
3x=1
x=1/3
2)3x+2=-3
3x=-3-2
3x=-5
x=-5/3

Answer 2

$(3x+2)^2 = 9 \\ \\ Not: 3x+2 = t \Rightarrow t^2 = 9 \Rightarrow t_{1,2} = \pm3 \\ t_1 = 3 \Rightarrow 3x+2 = 3 \Rightarrow 3x = 1 \Rightarrow \boxed{x_1 = \frac{1}{3} } \\ \\ t_2 = -3 \Rightarrow 3x+2=-3 \Rightarrow 3x = -5 \Rightarrow \boxed{x_2 = -\frac{5}{3}}$