Answer:
B and E
Step-by-step explanation:
∠ ECD = ∠ ACB ( vertically opposite angles are congruent ) , then
12x - 9 = 6x + 27 ( subtract 6x from both sides )
6x - 9 = 27 ( add 9 to both sides )
6x = 36 ( divide both sides by 6 )
x = 6 → B
Then
∠ ACB = 6x + 27 = 6(6) + 27 = 36 + 27 = 63° → E
