-2a - 3(b - 4a)

Answer 1

-2a-3(b-4a) .

-2b-3b-12a

10a-3b

Answer 2

-2a - 3(b - 4a) =

-2a - 3b + 12a (minus times minus = positive)

It is still 10a - 3b, but the middle step of carl had a typo.