Perpendicular is when a line is at a right angle to another. Parallel lines are side by side and even if they were to go on to infinity, would never meet. Therefore the answer is perpendicular.
A horizontal line is perpendicular to a vertical line.
*Straight Lines - Horizontal line - Vertical line - Broken line - Wavy line - Dotted line - Zigzag line - Diagonal line - perpendicular line - parallel line *Curved Lines - Concave line - Convex line - Spiral line
The perpendicular adjacent sides in the triangle would be 3 sides. It is the basically horizonstal line next to a vertical line(perpendicular) if it was parallel adjacent then only two side of triangle /\ <-- parallel
An horizontal line . A line parallel with the x-axis. NB A vertical line / a slope parallel with the y-axis is described as 'undefined'.
A vertical line goes North And South and a horizontal line goes East And West.