55 points
180 points
6 points
24 points
14 points
5 points
10 points
24 points
3 points
6 points
8 points
3 points
*
Only true in Cartesian coordinates.
A straight line in polar coordinates with the same tangent would be a circle.
EDIT: it is still a “straight” line. But then the result of a square on a surface is not the same shape any more.