Because the line goes on forever in both directions.
natural gas line
When surface datums are shown on extension lines, they are offset from dimension line arrows. Axis datums and center plane datums, on the other hand, can align with the dimension line's arrowheads.
Kites, arrowheads.
The only quadrilaterals with a reflex angle are arrowheads (or chevrons).
Straight line ending in arrowheads, means "place on straight grain of fabric."
arrowheads are used to indicate the end of a dimension line or leader
Because the line goes on forever in both directions.
The beauty of nature is indicated in line
My experience finding arrowheads was to walk the creek beds.
natural gas line
solid line
Solid Line
A straight line.
Arrowheads look like a triangle with the pointy head pointing away from the body.
Native Americans used arrowheads to make arrows and spears for hunting.
Graphically you'd draw a stylised satellite (in orbit) and satellite dish (on the ground), with a dashed line between the two. If the dish is both transmitter and receiver, use arrowheads in both directions. If it is a receiver only, arrowheads should point from the satellite to the dish.