(3x+2)(3x-4)=(2x+3)(3x-1)+(3x+1)(x-4) решить

1) ( 3х + 2 )( 3х - 4 ) = 9х^2 - 12х + 6х - 8 = 9х^2 - 6х - 8
2) ( 2х + 3 )( 3х - 1 ) = 6х^2 - 2х + 9x - 3 = 6x^2 + 7x - 3
3) ( 3x + 1 )( x - 4 ) = 3x^2 - 12x + x - 4 = 3x^2 - 11x - 4

9x^2 - 6x - 8 = 6x^2 + 7x - 3 + 3x^2 - 11x - 4
9x^2 - 6x - 8 = 9x^2 - 4x - 7
- 6x - 8 = - 4x - 7
6x - 4x = - 8 + 7
2x = - 1
X = - 0,5