Answer :
The length of HJ is 3.5 cm
What is Congruency?
Two geometric figures are said to be congruent, or to be in the relation of congruence, if it is possible to superpose one of them on the other so that they coincide throughout.
Given:
AB = 3.5 cm, BC = 2.4 cm, and AC = 4.2 cm
As, ΔABC ≅ ΔHJK
So,
AB = HJ
BC = JK
AC = HK
Thus, HJ= AB = 3.5 cm
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