Hey there!
Like I commented on your previous questions, you would have to use distributive property.
Multiply......
3xy × 4xy = 12x²y²
3xy × 2 = 6xy
-1 × 4xy = -4xy
-1 × 2 = -2
Add all those terms
12x²y² + 6xy - 4xy - 2
add the like terms
12x²y² + 2xy - 2
Hope this helped :)