Question

Identify the correct trigonometry formula to use to solve for x.11Х55°

Answer 1

From the right-angled triangle given, let us identify the given sides with reference to the angle 55°

`\begin{gathered} x\text{ is the hypotenus(the longest side opposite the right angle)} \\ 11istheadjacentsidetotheangle55^0 \end{gathered}`

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

`\begin{gathered} \cos A=\frac{Adjacent}{\text{Hypotenus}} \\ \cos 55^0=(11)/(x) \end{gathered}`