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प्रश्न
In ∆ABC, AB = 5 cm, BC = 8 cm and CA = 7 cm. If D and E are respectively the mid-points of AB and BC, determine the length of DE.
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उत्तर
In ΔABC, we have AB = 5 cm, BC = 8 cm and CA = 7 cm.
Since, D and E are the mid-points of AB and BC, respectively.
By mid-point theorem, DE || AC
And DE = `1/2` AC = `7/2` = 3.5 cm
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