Case 1 In 2D coordinate system the sum of the angles of all quadrants=360 degree in (x,y) plane Case 2 In 3D coordinate system (x,y,z) I took 3 possible planes i.e. (x,y) (y,z) (x,z) each plane provides angle of 360 degree, so can we say that in 3D coordinate system sum of all quadrants is 1080? Because (x,y) gives 360 (y,z) gives 360 (x,z) gives 360 so their sum is 1080 degree Case 3 And in 4d spacetime the distance formula according to Minkowski formulation is s^2=x^2+y^2+z^2-(ct)^2 Where c is speed of light and t is time and ct also has the dimension length like other coordinates. so can I deal it as a 4D coordinate system (x,y,z,ct) all possible planes are (x,y) (y,z) (z,ct) (x,ct) (y,ct) (x,z) so can we say, sum of all quadrants in 4D coordinate system is 2160 degree? Because each plane provides 360 degree & there are 6 planes. Three of them belong to 3D and 3 belong to space and time. Can I deal these coordinates in this way.