4 or 8 Four (the edges of the base square)
Perhaps four more, depending on the height of the pyramid, the opposing edges could be perpendicular to each other at the apex.
A square base pyramid has 8 perpendicular lines. These include the 4 edges of the square base perpendicular to each other and the 4 edges connecting the apex of the pyramid to each vertex of the base, which are also perpendicular to the base.
Including its diagonals there are 6 perpendicular lines
4
24
24
A square base pyramid has 8 perpendicular lines. These include the 4 edges of the square base perpendicular to each other and the 4 edges connecting the apex of the pyramid to each vertex of the base, which are also perpendicular to the base.
24
Including its diagonals there are 6 perpendicular lines
Do pyramids have perpendicular faces ?
4
24
24
24
4
Two pairs.
In a trapezium, there are two perpendicular lines. These perpendicular lines are the diagonals of the trapezium. The diagonals of a trapezium are the line segments that connect non-adjacent vertices of the trapezium and intersect each other at a right angle.
a square based pyrmaid has 24 lines of symitry