Odpowiedź :
a) 9x²-12x+4=0
(3x-2)²=0
3x-2=0
3x=2
x= ⅔
b) 25 x²+ 40x+16 =0
(5x+4)²=0
5x+4=0
5x= -4
x= -⅘
c) 4x²- 28x+49=0
(2x- 7)²=0
2x-7= 0
2x=7
x= 7/2= 3 ½
a) 9x²-12x+4=0
(3x-2)²=0
3x-2=0
3x=2
x= ⅔
b) 25 x²+ 40x+16 =0
(5x+4)²=0
5x+4=0
5x= -4
x= -⅘
c) 4x²- 28x+49=0
(2x- 7)²=0
2x-7= 0
2x=7
x= 7/2= 3 ½