a)
(4-3x)^2= 16- 3x^2
16-24x+9x^2=16-3x^2
9x^2-24x+3x^2=16-16
12x^2-24x=0 |:12
x^2-2x=0
x(x-2)=0
x=2
lub
x=0
b)
(3x + 2)^2 = 7(3x + 2)
9x^2+12x+4=21x+14
9x^2+12x-21x=14-4
9x^2-9x-10=0
rozwiazanie równania kwadratowego
\Delta=b^2-4ac=81-4*9*(-10)=81+360=441
\sqrt\Delta=21
x_1=\frac{-b-\sqrt\Delta}{2a}=\frac{9-21}{2*9}=\frac{-12}{18}=-\frac{2}{3}
x_2=\frac{-b+\sqrt\Delta}{2a}=\frac{9+21}{2*9}=\frac{30}{18}=\frac{5}{3}