help plz:

4. Multiply the following signed numbers:

a. (-42x)(+2x) =

b. (+7x)(-4x)(-3x) =

c. (+7)(-4)(-4) =

d. (+10)(-2)(-2)(+4) =

help plz:

4. Multiply the following signed numbers:

a. (-42x)(+2x) =

b. (+7x)(-4x)(-3x) =

c. (+7)(-4)(-4) =

d. (+10)(-2)(-2)(+4) =

Answer:Step-by-step explanation:Answer: