What is the angle between these two vectors?

[IDKFysics]

Vectors A and B have scalar product -4.00 and their vector product has magnitude 9.00.

Here's what I did:

ABcos=-4
ABsin=9

sin/cos=-2.25

tan=-2.25

angle=-66?

I entered this and it says it's incorrect. What did I do wrong?

 

[N2O2]

Pay attention that the angle between two vectors won't be negative ...

There should be an angle that its cos is - and its sin is +

angle: 180 - 66 = 114 degree