Answer:
6sqrt(3) = b
a= 6
Step-by-step explanation:
Just apply Soh Cah toa
opposite = a
sin(30) = opposite/hypotenuse
sin(30) = a/12 a= 6
Then do pythagoras
b^2 + 6^2 = 12^2
144-36 = 108
sqrt(108) = sqrt(36*3) = 6sqrt(3) = b
Hope that answers your question