So since they mentioned tangent I am guessing you need to use sin and cosine.
Usually we use sin, cosine and tan when we have an angle and we need to find one of the sides (look at the picture below)
But since now we have the sides and we need to find the angle, we need to use something called sin inverse or arcsin.
X=sin^-1 (6/14)
Note: sin^-1 is the same as saying sine inverse same as saying arcsin.
If we use this it will give us the required angle..
X=25.377 or X=25.4 degrees
Please do yourself a favour and compare it to the one below...finding the sides (because in the case we have the angle and not the sides we don’t use sine inverse)