bonjour,
1) (x-1)(3x+2)+(-1+x)(1-2x) = 0
(x-1)(3x+2+1-2x) = 0
(x-1)(x+3) = 0
x = 1 ; -3
(3x + 2)² - 9x² = 0
(3x+2-3x)(3x+2+3x) = 0
2(6x+2) = 0
x = -2/6 =-1/3
(8x + 3)²=(9x - 2)² =
(8+3x)²-(9x-2)² = 0
(8+3x-9x+2)(8+3x+9x-2) = 0
(-6x+10)(12x+6) = 0
x = 5/3 ; -1/2