1)9x-25y=2)(x+2y)=3)27x^3+8y^3=4)(5x-6y)=5)x^6-y^3=

1)9x^2 - 25y^2=(3x-5y)(3x+5y),  

9x^2+30xy+25y^2=(3x+5y)^2.

2)x2 - y2 = (x - y)(x + y)

x2 + y2 = здесь нет таковой формулы

3) ((27*x^3+8*y^3)/(9*x^2-6*x*y+4*y^2))-3*x =((3*x+2*y)*(9*x^2-6*x*y+4*y^2))/(9*x^2-6*x*y+4*y^2)-3*x=(3*x+2*y-3*x)=2*y;

4)= (5x - 6y - 5x - 6y)(5x - 6y + 5x + 6y) =  

= - 12y * 10x =  

= - 120xy

5)4x+3y-36=0

3y=36-4x /3

y=12-4x/3

x-6y+3=0

6y=x+3

y=x+3/6