i feel like i should know this one...
any kind of help is appreciated :)

Answer:
∠TAC = 70.53°
Step-by-step explanation:
ABCD is a square: AC = √AB²+BC² = √72
AM = 1/2 AC = √72 / 2 = 3 √2
tan ∠TAC = TM / AM = 12 / 3 √2 = 2.8284
∠TAC = 70.53°