Answer
(a) We can see the point $(2,\frac{5\pi}{6})$ on the graph.
Two other pairs of polar coordinates are $(2, \frac{17\pi}{6})$ and $(-2, \frac{11\pi}{6})$
(b) We can see the point $(1,-\frac{2\pi}{3})$ on the graph.
Two other pairs of polar coordinates are $(1, \frac{4\pi}{3})$ and $(-1, \frac{\pi}{3})$
(c) We can see the point $(-1,\frac{5\pi}{4})$ on the graph.
Two other pairs of polar coordinates are $(1, \frac{\pi}{4})$ and $(-1, \frac{13\pi}{4})$
Work Step by Step
(a) We can see the point $(2,\frac{5\pi}{6})$ on the graph.
We can find two other pairs of polar coordinates:
$(2, \frac{5\pi}{6}+2\pi) = (2, \frac{17\pi}{6})$
$(-2, \frac{5\pi}{6}+\pi) = (-2, \frac{11\pi}{6})$
(b) We can see the point $(1,-\frac{2\pi}{3})$ on the graph.
We can find two other pairs of polar coordinates:
$(1, -\frac{2\pi}{3}+2\pi) = (1, \frac{4\pi}{3})$
$(-1, -\frac{2\pi}{3}+\pi) = (-1, \frac{\pi}{3})$
(c) We can see the point $(-1,\frac{5\pi}{4})$ on the graph.
We can find two other pairs of polar coordinates:
$(1, \frac{5\pi}{4}-\pi) = (1, \frac{\pi}{4})$
$(-1, \frac{5\pi}{4}+2\pi) = (-1, \frac{13\pi}{4})$
