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Triangle ABC is right-angled at vertex A. Calculate the length of BC, if AB = 18 cm and AC = 24 cm.

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#### Solution

**Given: **∆ ABC right angled at A and AB = 18 cm, AC = 24 cm.

**To find:** Length of BC.

According to Pythagoras Theorem,

BC^{2} = AB^{2} + AC^{2}= 18^{2} + 24^{2 }= 324 + 576 = 900

∴ BC =`sqrt900=sqrt(30xx30)` = 30 cm

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