Confused about Question 1 from I'm overwhelmed Mod 8 pt 1 - seemingly impossible question

[user11440]

I’m confused as to why is the base opposite of 30 = 3 root 3 instead of just 3 since 30-60-90 triangles are x- root 3(X) - 2X

[Kweku]

Base, as described in the solution is BC, not AC.

AC is the height.