chấm điểm giúp mk nhé
a/ 2x² - 2xy +5x - 5y
= 2x(x-y) + 5(x-y)
= (2x+5)(x-y)
c/ x²-x-9y^2 + 3y
= (x-3y)(x+3y) -(x-3y)
=(x-3y)(x+3y-1)
b/ x²-y² +2x-2y
= (x-y)(x+y) +2(x-y)
=(x-y)(x+y+2)
d/ x^3-x+y³-y
= (x+y)(x^2 -xy+y^2) -(x+y)
=(x+y)(x^2 -xy+y^2 -1)

a/ 2x^2 - 2xy + 5x - 5y
= 2x(x - y) + 5.(x  y)
= (x - y).(2x +5
b/ x^2 - y^2 + 2x - 2y
= ( x- y).(x +y) + 2.(x - y)
= (x - y).(x + y +2)
c/ x^2 - x - 9y^2 + 3y
= x^2 - 9y^2 - x + 3y
= (x - 3y).(x +3y) - (x - 3y)
= (x - 3y).(x + 3y - 1)
d/ x^3 - x + y^3 - y
= (x +y)(x^2 - x + y^2) - (x +y)
= (x +y).(x^2 - x + y^2)

a) = 2x(x - y) + 5(x - y)
= (x - y)(2x + 5)
b) = (x^2 - y^2) + 2(x - y)
= (x - y)(x + y) + 2(x - y)
 = (x - y)(x + y +2)
c) = (x^2 - 9y^2) - (x - 3y)
= (x -3y)(x + 3y) - (x - 3y)
= (x - 3y)(x + 3y - 1)
d) = (x^3 + y^3) - (x + y)
= (x + y)(x^2 - xy + y) - (x + y)
= (x + y)(x^2 - xy + y - 1)