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Question
In Fig. below, M, N and P are the mid-points of AB, AC and BC respectively. If MN = 3 cm, NP = 3.5 cm and MP = 2.5 cm, calculate BC, AB and AC.

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Solution

Given MN = 3cm, NP = 3.5cm and MP = 2.5cm
To find BC, AB and AC
In ΔABC
M and N are midpoints of AB and AC
∴MN = `1/2` BC, MN || BC [By midpoint theorem]
⇒ 3 = `1/2` BC
⇒ 3× 2 = BC
⇒ BC = 6cm
Similarly
AC = 2MP = 2 (2.5) = 5cm
AB = 2NP = 2(3.5) = 7cm
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