(2x-4xy): 2 =2(x-2xy):2=x-2xy
(6a - 9ab +1) : (-3)=-3(-2a+3ab-\frac{1}{3})=-2a+3ab-\frac{1}{3}
(2x^2-4x-10) : \frac{2}{3}=(2x^2-4x-10)*\frac{3}{2}=2(x^2-2x-5)*\frac{3}{2}=3x^2-6x-15
\frac{12xy-20x}{4}=\frac{4(3xy-5x)}{4}=3xy-5x
\frac{10a +5b -15}{-5}=\frac{-5(-2a-b+3)}{-5}=-2a-b+3
\frac{8x^2-x+36}{4}=2x^2-\frac{1}{4}x+9
30*\frac{c^2-3c+2}{5}=6(c^2-3c+2)=6c^^2-18c+12
-4*\frac{3(x+1)}{2}=-2* 3(x+1)=-6(x+1)=-6x-6