paradiseva

Verified answer

9m-yn+yn-9n = 9m - 9n = 9(m-n)
x*x-6xy+9y*y-9 = x^2 -6xy + 9y^2 - 9 = x^2 - 2*3xy + (3y)^2 - 9 = (x-3y)^2 - 9 = (x-3y-3)*(x-3y+3)
a*a*a(b-1)-b+1 = a^3(b-1) - b + 1 = a^3(b-1) - (b -1) =(b-1)(a^3-1) 
3x*x-24x+48 = 3x^2 - 24x + 48 = 3(x-4)^2