Answer:
see below
Explanation:
Perpendicular lines are where two lines meet at right angles and form a 90 degree corner.
Books have perpendicular lines meeting at corners. The top and side edges.
Desks that have corners, like a teachers desk.
The sides of tiles meet at 90 degree angles.
The top and side of the flag meet at a 90 angle so they would be perpendicular lines.