# What is the polar form of (11,-8)?

($\sqrt{185}$, 324)
Plot the point (11,-8) and then draw a line from the origin to that point. Use the Pythagorean Theorem to calculate the length of this line segment. The answer, $\sqrt{185}$, is your r value.
Then, find θ using some basic trig (again, I'm assuming you have a good grasp of the primary trig ratios and how to use them in right triangles). From your drawing, you should see that the angle clockwise from the positive x-axis to your line segment is equal to ${\tan}^{-} 1$ (8/11) or approximately 36 degrees. In order to find the angle counterclockwise from the positive x-axis (as mathematicians virtually always do), subtract 36 from 360. The difference, 324, is your value for θ. Hence the polar coordinates you're looking for are ($\sqrt{185}$, 324).