In the Given Figure, Angle Adb = 90°, Ac = Ab = 26 Cm and Bd = Dc. If the Length of Ad = 24 Cm; Find the Length of Bc. - Mathematics

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Sum

In the given figure, angle ADB = 90°, AC = AB = 26 cm and BD = DC. If the length of AD = 24 cm; find the length of BC.

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Solution

Given:
∆ ABC
∠ADB = 90° and AC = AB = 26 cm
AD = 24 cm

To find : Length of BC In right angled ∆ ADC
AB = 26 cm, AD = 24 cm
According to Pythagoras Theorem,
(AC)2 = (AD)2 + (DC)2
(26)2 = (24)2 + (DC)2
676 = 576 + (DC)2
⇒ (DC)2 = 100
⇒ DC =`sqrt100` = 10 cm
∴ Length of BC = BD + DC
= 10 + 10 = 20 cm

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Chapter 16: Pythagoras Theorem - Exercise 16

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Selina Concise Mathematics Class 7 ICSE
Chapter 16 Pythagoras Theorem
Exercise 16 | Q 10

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