Constructions — Maths STD 7 — Question

Steps of construction:
Step I: We first draw a triangle ABC with each side = 6cm.
Steps to bisect line AB:
Step I: Draw an arc from A on either side of line AB.
Step II: With the same radius as in the previous step, draw an arc from B on either side of AB intersecting the arcs drawn in the previous step at P and Q.
Step III: Join PQ cutting AB at D. PQ is the perpendicular bisector of AB.
Parallel line to BC:
Step I: With B as centre, draw an arc cutting BC and BA at M and N, respectively.
Step II: With centre D and the same radius as in the previous step, draw an arc on the opposite side of AB to cut AB at Y.
Step II: With centre Y and radius equal to MN, draw an arc cutting the arc drawn in the previous step at X.
Step III: Join XD and extend it to intersect AC at E.
Step IV: DE is the required parallel line.