To convert the rectangular coordinates (3, -3) into polar coordinates, we follow a systematic approach. First, we plot the point on the rectangular coordinate system, which is located in the fourth quadrant.

Next, we calculate the radial distance \( r \) using the formula:

\[ r = \sqrt{x^2 + y^2} \]

Substituting the values \( x = 3 \) and \( y = -3 \), we find:

\[ r = \sqrt{3^2 + (-3)^2} = \sqrt{9 + 9} = \sqrt{18} = 3\sqrt{2} \]

Now, we determine the angle \( \theta \). Since the point is in the fourth quadrant, we use the inverse tangent function:

\[ \theta = \tan^{-1}\left(\frac{y}{x}\right) = \tan^{-1}\left(\frac{-3}{3}\right) = \tan^{-1}(-1) \]

This simplifies to:

\[ \theta = -\frac{\pi}{4} \]

It is important to note that angles in polar coordinates can be represented in multiple ways. For instance, the angle \( -\frac{\pi}{4} \) can also be expressed as \( \frac{7\pi}{4} \), which is equivalent and represents the same point. Thus, the polar coordinates for the point (3, -3) can be written as:

\[ (3\sqrt{2}, -\frac{\pi}{4}) \] or \[ (3\sqrt{2}, \frac{7\pi}{4}) \]

Both representations are valid, and converting back to rectangular coordinates will yield the original point (3, -3).