Determining the horizontal and vertical trace of the line P2’’ 1x2 q” q’ Q1’ p’’ Q2” P1’’ 1x2 P2’ Q1” Q2’ P1’ p’

Exercise 1 Construct the orthogonal projection of the straight line q passing through point T, parallel to the plane 1 and intersecting the given straight line p. p’’ p’ T’’ T’ q’’ S’’ S’ 1x2 q’

Exercise 2 Construct the orthogonal projection of the straight line p that intersects the line g in the point A(1,-,-) and is parallel to 1 i 2. Straight line g is given with points F(4,1,1) i G(0,3,3). 1 G’’ F’’ F’ G’ A’ A’’ p’’ p’ g’’ g’ 1x2

Exercise 3 Construct a line segment of length d on a straight line p starting at point T. p’’ B’’ A’’ d’’ d T’’ P1’’ P1’ p0 Instructions. True length of a line segment can be determined from a projection of the line only in the line is in a projection plane or parallel to . Otherwise, if a straight line is in an arbitrary position, for determining the true length it is nessesary to rotate the line into the projection plane. A’ B’ 1x2 d’ B0 d T’ T0 d p’ A0

Angles of inclination of a straight line to the planes of projection The line can be rotated using any point incident with it, but it is common to use its horizontal or vertical trace. P2’’ 2 p0 p’’ A” A’ P10 P1’’ 1x2 1= (p,p’) P2’ P1’ 2= (p,p’’) . p’ 1 p0 A0 P20

Exercise 4 Let a straight line p be given with points A(2,3,4) i B(5,-1,2). Determine its horizontal, vertical trace and first angle of inclination. p0 P1’ p’ p” A’ A” P2” B’ B” 1 1 1x2 P’2 P”1 A0