Triangle Abc is Right-angled at Vertex A. Calculate the Length of Bc, If Ab = 18 Cm and Ac = 24 Cm. - Mathematics

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Sum

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,
BC2 = AB2 + AC2
= 182 + 24= 324 + 576 = 900
∴ BC =`sqrt900=sqrt(30xx30)` = 30 cm

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Chapter 16: Pythagoras Theorem - Exercise 16

APPEARS IN

Selina Concise Mathematics Class 7 ICSE
Chapter 16 Pythagoras Theorem
Exercise 16 | Q 1

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