Let \( \alpha \) and \( \beta \) be planes sharing three different points \( A \), \( B \), and \( C \). The points do not lie on one line. What is the mutual position of these two planes?
Let \( ABCDEFGH \) be a cube and \( M \), \( N \), and \( P \) the midpoints of the edges \( BF \), \( EF \), and \( CD \), as seen in the picture. What is the mutual position of the lines \( DM \) and \( NP \)?
Let \( ABCDEFGH \) be a cube and \( L \), \( M \) the midpoints of the edges \( AB \) and \( BF \). See the picture. What is the mutual position of lines \( DL \) and \( GM \)?
Let \( ABCDEFGH \) be a cube and \( N \) the midpoint of the edge \( EF \). See the picture. What is the mutual position of lines \( BN \) and \( CF \)?
Let \( ABCDEFGH \) be a cube and \( X \), \( Z \) the midpoints of the edges \( FB \) and \( FG \). See the picture. What is the mutual position of lines \( XZ \) and \( AH \)?
Let \( ABCDEFGH \) be a cube and \( K \), \( L \) the centers of its faces \( ABCD \) and \( BCGF \) consecutively as seen in the picture. What is the mutual position of a line \( KL \) and a plane \( CDH \)?
Let \( ABCDEFGH \) be a cube and \( L \), \( N \) the centers of its faces \( BCGF \) and \( ADHE \) consecutively as seen in the picture. What is the mutual position of the line \( LN \) and the plane \( ABG \)?
Let \( ABCDV \) be a rectangle based-pyramid, \( V \) is its apex and \( K \), \( L \), and \( M \) are the midpoints of its edges \( AB \), \( BC \), and \( AD \) as seen in the picture. What is the mutual position of the line \( KL \) and the plane \( CV\!M \)?