Question

On a circle, a line is drawn from the origin to A(-3,4). The angle Ø is between the line and the x- axis. Find Cos Ø

Answer 1

Therefore,

`\cos \phi=\frac{Adjacent}{\text{hypotenuse}}`

But, we do not have the dimension for the hypotenuse, In order to find the hypotenuse, we need to apply the Pythagorean theorem

Hence,

`\begin{gathered} \text{Hyp}^2=opp^2+adj^2 \\ \text{hyp}^2=4^2+3^2 \\ \text{hyp}^2=16+9 \\ \text{hyp}^2=25 \\ \text{hyp}=\sqrt[]{25} \\ =5 \end{gathered}`

Therefore,

`\cos \phi=(3)/(5)`