Question

In triangle ABC, AB=8cm,

Answer 1

FIND OC

By Phythagoras theorem,

In △ABO,AB2=AO2+BO2.....(1) and 

In △ACO,AC2=AO2+OC2.....(2)

Subtracting equation 2 from 1, we get,

AB2−AC2=AO2−AO2+BO2−OC2

⇒AB2−AC2=BO2−OC2

⇒82−32=(BC+OC)2−OC2

⇒55=(BC+OC)2−OC2

⇒55=BC2+OC2+2BC×OC−OC2

⇒55=62+2×6×OC

⇒55−36=12×OC

⇒12×OC=19

⇒OC=19÷12=1.583∼1.6cm