x^-8xy+15y^+2x-4y-3
x^-8xy+15y^+2x-4y-3
=x^-8xy+16y^- y^+2x-4y-3
=(x-4y)^- y^+2y-1-(2y-1)+2x-4y-3
=(x-4y)^-(y-1)^+2x-6y-2
=(x-4y-(y-1)) (x-4y+(y-1))+2(x-3y-1)
=(x-5y+1) (x-3y-1)+2(x-3y-1)
=(x-5y+1+2) (x-3y-1)
=(x-5y+3) (x-3y-1)
x^-8xy+15y^+2x-4y-3
=x^-8xy+16y^- y^+2x-4y-3
=(x-4y)^- y^+2y-1-(2y-1)+2x-4y-3
=(x-4y)^-(y-1)^+2x-6y-2
=(x-4y-(y-1)) (x-4y+(y-1))+2(x-3y-1)
=(x-5y+1) (x-3y-1)+2(x-3y-1)
=(x-5y+1+2) (x-3y-1)
=(x-5y+3) (x-3y-1)