Q9 of 168 Page 4

Using Pythagoras theorem determine the length of AD in terms of b and c shown in Fig 4.219.

In ABC


BC2=AB2+AC2


BC2=c2+b2


BC= ………………(i)


In ABC and In CBA


∠B= ∠B (Common)


∠ADB=∠BAC=90°


∴ ABD ~ CBA


∴ AB/CB=AD/CA


c/ =AD/b


AD=bc/


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