SOLUTION: Find the missing coordinate of P(−1, ) using the fact that P lies on the unit circle in quadrant III

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Question 1155050: Find the missing coordinate of P(−1, ) using the fact that P lies on
the unit circle in quadrant III
Found 2 solutions by mananth, Theo:
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
since point lies on unit circle
x%5E2+%2By%5E2=1
x=-1
+1%5E2+%2By%5E2=1
y=0

Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
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.
https://etc.usf.edu/clipart/43200/43215/unit-circle7_43215.htm
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.