The graphic below shows a group of fishermen - Leaving Cert DCG - Question A-2 - 2018

Draw Line from A Parallel to CD (or C Parallel to AB) in Elevation

• Begin by sketching a line from point A parallel to line CD in the elevation view. This visually indicates how A extends towards CD without intersecting.

Draw Line from A Parallel to CD (or C Parallel to AB) in Plan

• In the plan view, extend a line from point A towards CD maintaining parallelism. This sets a clear perspective of where A and CD relate horizontally.

Determine Plane of Horizontal Line on Either Plane

• Identify a plane that can accommodate the shortest line twisting between A and CD, focusing on horizontal connectivity.

Identify X, Y Coordinates Perpendicular to Horizontal Line as Located

• Designate points based on the coordinates, identifying the perpendicular foot of the shortest line from X (A's projection) to Y (CD's projection).

Projections of AB and CD on X1Y1

• Mark projections of lines AB and CD on the designated plane X1Y1, ensuring accurate intersections and lengths are observed.

X1Y2 Perpendicular to X1Y1

• Establish a perpendicular intersection from the coordinate identified above to highlight dimensional differences, validating visual relations between all lines.

Projections of AB and CD on X1Y2

• Repeat the projection methodology for line AB and CD on the new plane X1Y2, further clarifying spatial relationships.

Projection of Required Shortest Horizontal Distance to Plan and Elevation

• Finally, provide the exact measurement for the horizontal distance derived from the interactions, presenting accurate distances in both the plan and elevation views.