DD' || AA' => m (DD' ; AA' ) =0 grade
m(AB ;BC ) = m ( ABC) = 90 grade
BC || B'C' => m ( A'D' ; BC ) = m ( A'D' ; B'C' ) => sunt paralele = 0 grade
AB || A'B' => m ( A'D' ; AB ) = m ( A'D' ; A'B' ) = m ( B'A'D' ) = 90 grade
BC || B'C' => m (A'B' ; BC ) = m ( A'B' ; B'C' ) = m (A'B' ; B'C' ) = m ( A'B'C' ) = 90 grade
SPER CA TE.AM AJUTAT !!