9x^2-4=0 2x^2=3x 2=7x^2+2 (2x+1)(x-4)=(x-2)(x+2)

9x^2-4=0
9x^2 = 4  /:9
x^2 = 4/9
x= ± 2/3

2x^2=3x
2x^2 -3x = 0
x (2x - 3) = 0
x= 0 либо x = 1,5

2=7x^2+2
7x^2 = 0 /:7
x^2 = 0
x= 0

(2x+1)(x-4)=(x-2)(x+2)
2x^2-7x - 4 = x^2 - 4
x^2 - 7x =  0
x (x - 7 ) = 0
x=0 либо x = 7

9х²-4=0
9х²=4
х²=4/9
х=±2/3

2х²=3х
2х²-3х=0
х(2х-3)=0
х1=0
х2=1,5

2=7х²+2
-7х²=0
х=0

2х²-8х+х-4=х²-4
х²-7х=0
х(х-7)=0
х1=0
х2=7