Projections of points in the final representation:

After the points are projected and the hitting is done, the final representations of the points are as shows this image. Note that points A, B, C and D are located at dihedrals I, II, III and IV, respectively.

Projections after hitting:

Rotating around the x-axis, the projection planes
they coincide. In this movement, called
by hitting, the dihedral I and III open, the dihedral
II and IV close.

The two coordinates of the point:

To represent points (and the other geometric figures) three coordinates are considered: x-axis, clearance and quota.

Here it is explained what the distance and the quota consist of. The x-axis is explained later in “The three coordinates of a point”.

Sometimes, to represent points (and other figures) the three coordinates are not always used, it is enough to work only with clearances and quotas, as it happens here.

Coordinate measurements are given in centimetres

Projections of the given points:

As can be seen, positive dimensions and negative spacing lead to projections up the x-axis; positive departures and negative quotas originate projections down the x-axis.