To find the coordinates of point \( C \) given its reflection point \( C' \) across the x-axis, we remember that when a point \( (x, y) \) is reflected across the x-axis, the resulting point is \( (x, -y) \).
Given that \( C' = (2, -2) \), we can find the coordinates of point \( C \) by reflecting \( C' \) back across the x-axis.
- The x-coordinate of \( C \) remains the same as that of \( C' \): \( x = 2 \).
- The y-coordinate of \( C \) is the opposite of that of \( C' \): \( y = -(-2) = 2 \).
Thus, the coordinates of point \( C \) are:
\[ C = (2, 2) \]
So, the coordinates of point \( C \) are \( \boxed{(2, 2)} \).