For this problem, you need to know how to use sin, cos, and tan or 'SOH-CAH-TOA' sin- opposite/hypotenuse cos-adjacent/hypotenuse toa- opposite/adjacent
in this case, you can use tan or toa
the equation should be set up like this:
4/x=1/0.848
solve, and you will get 3.39...
(you need to use the sin,cos,tan degree chart to find 0.848)