Your "set-up" is almost correct.....
But what does the tangent involve?? opposite and adjacent
And what are we looking for?? the hypoteneuse ....the length of the wire
What do we know?? an angle and the opposite side
And what function relates the opposite side and the hypoteneuse??
See if you can take it from here...
(I find it's helpful to draw a picture...also.....make sure you know your basic identities!!)