решение
(x - 1)(x + 2) = (x - 1)(2x + 3)
(x - 1)(x + 2) - (x - 1)(2x + 3) = 0
(x - 1)(x + 2 - 2x - 3) = 0
(x - 1)(-x - 1) = 0
-(x - 1)(x + 1) = 0
x = +-1
ответ: -1; 1.
решение
(x - 1)(x + 2) = (x - 1)(2x + 3)
(x - 1)(x + 2) - (x - 1)(2x + 3) = 0
(x - 1)(x + 2 - 2x - 3) = 0
(x - 1)(-x - 1) = 0
-(x - 1)(x + 1) = 0
x = +-1
ответ: -1; 1.