Answer:
13.6
Explanation:
Remember SOH CAH TOA
We're going to use tangent = opposite / adjacent because the 11 is opposite theta (39 degrees) and x is adjacent to it.
tan (39) = 11 / x
x = 11 / tan(39)
x = 13.584 -> 13.6 (rounded to nearest tenth)
Note: Make sure your calculator is in degree mode.