Construct Δ ABC, such that BC = 6 cm, ∠ABC = 100° and AC - AB = 2.5cm.
Steps of construction:
(1) Draw seg BC of length 6 cm.
(2) Draw ray BE such that ∠CBE = 100°
(3) Take point D on the opposite of ray BE such that BD = 2.5 cm.
(4) Construct perpendicular bisector of seg DC.
(5) Name the point of intersection of ray BE and the perpendicular bisector of DC as A.
(6) Draw seg AC.
Therefore, △ABC is required triangle.