Question

what are three different representations of (4, 30) on a polar graph?

Answer 1

\[x = r \cos \theta, y = r \sin \theta\]
Here x = 4, y = 30.

Answer 2

you need to solve for r and theta

Answer 3

if you add a multiple of 360º to the angle, you get the same point. So there are lots of different ways to write the same number in polar coordinates.

Answer 4

ohhh i get it so it's more like this (x=rcosø), y=rsinø) they're like coordinates?

Answer 5

if (4,30) represents r and theta, then add 360 to the angle
if (4,30) is rectangular coordinates, you need to change to polar form.

Answer 6

the polar coordinate would be (r, theta)

Answer 7

no no i get that they are polar coordinates but all I do is add 360? won't that give me the same number?

Answer 8

i mean unless I go farther. Is one of them (4, 390)?

Answer 9

yes (4,390) is another "representation" for the point (4,30)

Answer 10

okay! thanks!

Answer 11

you can also add 720 degrees
or subtract 360

or, slightly more complicated, add 180º and change the sign of r:
(-4, 210º)
for example. But it is best not to use negative r values. (you can always make them positive by adding or subtracting 180º from the angle)

Answer 12

okay awesome! I think I get it now!

Answer 13

yw