Question 27853
According to distributive property a(b+c-d) = ab + ac - ad

Similarly 
-2u(3v-4w-3x)
is simplified to

3v *(-2u) - 4w*(-2u) -3x*(-2u)

-6uv +8uw + 6xu

( I have used * to denote multiplication)
note that -4 * -2 = +8; and -2*-3 = +6 )

Hope this helps!