Constructions — Maths STD 7 — Question

Steps of construction:
Step I: Mark three non collinear points A, B and C such that none of them lie on the same line.
Step II: Join AB, BC and CA to form triangle ABC.
Step III: Parallel line to AC
Step IV: With A as centre, draw an arc cutting AC and AB at T and U, respectively.
Step V: With centre B and the same radius as in the previous step, draw an arc on the opposite side of AB to cut AB at X.
Step VI: With centre X and radius equal to TU, draw an arc cutting the arc drawn in the previous step at Y.
Step VII: Join BY and produce in both directions to obtain the line parallel to AC.
Parallel line to AB:
Step I: With B as centre, draw an arc cutting BC and BA at W and V, respectively.
Step II: With centre C and the same radius as in the previous step, draw an arc on the opposite side of BC to cut BC at P.
Step III: With centre P and radius equal to WV, draw an arc cutting the arc drawn in the previous step at Q.
Step IV: Join CQ and produce in both directions to obtain the line parallel to AB.