Mathematics for IGCSE & O level - Mensuration (Section 8 - No. 15)
What is meant by 'perpendicular height'?
A line that meets another at an angle of 45 degrees.
A line that is parallel to the base.
A line that forms a right angle with the base.
A line that is the same length as the base.
Explication
Perpendicular means forming a right angle (90 degrees).