Answer:
15a - 12
Step-by-step explanation:
7a - 4 [ 2 - (2a - 1) ] ← distribute parenthesis inside the bracket by - 1
= 7a - 4 [ 2 - 2a + 1 ]
= 7a - 4 (- 2a + 3) ← distribute parenthesis by - 4
= 7a + 8a - 12 ← collect like terms
= 15a - 12