ANSWER
[tex]x=66.4^o[/tex]EXPLANATION
We want to use the inverse cosine function to find the value of x.
If the cosine of an angle is:
cos(x) = a
then, the inverse cosine function is:
[tex]\cos ^{-1}(a)\text{ = x}[/tex]So, we have that:
[tex]\begin{gathered} \cos ^{-1}(0.4)\text{ = x} \\ \Rightarrow x=66.4^o \end{gathered}[/tex]That is the answer.
