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Question
In a right angled triangle, right-angled at B, lengths of sides AB and AC are 5 cm and 13 cm, respectively. What will be the length of side BC?
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Solution
Given: ∠ABC = 90°, AB = 5 cm, AC = 13 cm.
According to the Pythagoras theorem,
AB2 + BC2 = AC2
⇒ 52 + BC2 = 132
⇒ 25 + BC2 = 169
⇒ BC2 = 169 – 25 = 144
⇒ BC = `sqrt(144)` = 12
Hence, the length of side BC is 12 cm.
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