Question 1155050
the unit circle is a circle with a radius of 1.
this means that x^2 + y^2 = 1
if x is minus 1, then you get (-1)^2 + y^2 = 1
simplify to get 1 + y^2 = 1
solve for y to get y = sqrt(0) = 0.
the coordinate is (-1,0)
here's a picture of the unit circle that shows that.
<a href = "https://etc.usf.edu/clipart/43200/43215/unit-circle7_43215.htm" target = "_blank">https://etc.usf.edu/clipart/43200/43215/unit-circle7_43215.htm</a>
you can see that when x = -1, y = 0.
the angle formed is 180 degrees.
actually P is on the border between quadrant II and III.