1)a²-6ab+9b²=(a-3b)²
2)x(a-b)+y(a-b)=(a-b)(x+y)
3)(x-3)-y(x-3)=(x-3)(1-y)
4)5(c-4)+x(4-c)=5(c-4)-x(c-4)=(c-4)(5-x)
5)x-p+(p-x)c=x-p-(x-p)c=(x-p)(1-c)
6)ax-ay+bx-by=a(x-y)+b(x-y)=(x-y)(a+b)
7)2x+7y+14+xy=2x+14+xy+7y=2(x+7)+y(x+7)=(x+7)(2+y)
8)2x-ac-cx+2a=2x+2a-ac-cx=2(x+a)-c(a+x)=(x+a)(2-c)
9)a(x+y)=ax+ay
10)-p(a-b)=-ap+bp
11)3x²(x³-3)(-5xˇ4)=-15xˇ9 + 45xˇ6
12)3x(x-2)-5x(x+3)=3x²-6x-5x²-15x=-2x²-21x
13)5n²(3n-1)-2n(5n²-3)=15n³-5n²-10n³+6n=5n³-5n²+6n