Hey there!!
The person who answered first is almost completely correct, the only part that is off is 10xy…
Solution:
(3xy - 1) (4xy + 2)
(3xy)(4xy) + (3xy)(2) + (-1)(4xy) + (-1)(2)
12xy² + 6xy + -4xy + -2
Answer:
12x²y² + 2xy + -2
So I found that you need to add 6 and -4, not subtract to get 2xy as part of the answer.
I hope this helped answer some of your inquiries!!! God bless!