Q4 of 109 Page 330

In a ΔABC, D and E are the mid-points of AB and AC respectively and DE = 5.6 cm. Find the length of BC.

We know that in ∆ABC, D and E are the midpoints of AB and AC, respectively.

Now using mid-point theorem,


DE = (BC)


BC= 2 ⨯ DE


BC= 2 ​⨯ 5.6


= 11.2 cm


Thus, BC = 11.2 cm


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