From the right-angled triangle given, let us identify the given sides with reference to the angle 55°
[tex]\begin{gathered} x\text{ is the hypotenus(the longest side opposite the right angle)} \\ 11istheadjacentsidetotheangle55^0 \end{gathered}[/tex]
The correct trigonometry that has both the adjacent and the hypotenuse is the cosine
To solve for x, we will then use cosine as follows
[tex]\begin{gathered} \cos A=\frac{Adjacent}{\text{Hypotenus}} \\ \cos 55^0=\frac{11}{x} \end{gathered}[/tex][tex]undefined[/tex]
