(2x+7) (3x-1)-(5x-1) (x+3)=(x+1)

Question

(2x+7) (3x-1)-(5x-1) (x+3)=(x+1)

Answer 1

(2x+7) (3x-1)-(5x-1) (x+3)=(x+1),6x² +21x -2x - 7 - (5x² - x + 15 x - 3) - x - 1 = 0,

6x² +21x -2x - 7 - 5x² + x - 15 x + 3 - x - 1 = 0,

x² + 4x - 5 = 0,
D=16 - 4·(-5)=36=6²
x = (-4-6)/2= -5 ,   x = (-4+6)/2=1
Ответ. х= - 5, х=1