Question

The point P=(-45(square root)/7,y) lies on the unit circle shown below. What is the value of y in simplest form?You might have to zoom into the photo to un-blur it.

Answer 1

Given the figure of the unit circle

So, the radius of the circle = 1

The point p has the coordinates:

`P\colon(-\frac{\sqrt[]{45}}{7},y)`

so,

`(-\frac{\sqrt[]{45}}{7})^2+y^2=1`

solve for y:

`\begin{gathered} y^2=1-(45)/(49)=(4)/(49) \\ \\ y=\pm\sqrt[]{(4)/(49)}=\pm(2)/(7) \end{gathered}`

For the shown point P

so, the answer will be y = -2/7