Verified Answer :

2/3 (6e + 9f -21g) -7f

2/3 (6e-56f -21g)

Multiply each coefficient by 2/3 for the numbers in parenthesis.
So 2/3 6 = 12/3 = 4, 2/3 9 = 18/3 = 6, 2/3*21 = 42/3 = 14.

That simplifies to 6e + 9f - 14 g - 7f.

Add like terms to get 6e + 2f - 14g.