Please solve q 38 ?

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1 Answer
Jul 1, 2018

rarrBE=EC As E is the mid point of BC.

In rt Delta ABE,

rarrAB^2=AE^2+BE^2

In rt DeltaADE,

rarrAD^2=AE^2+ED^2

LHS=AB^2-AD^2

=AE^2+BE^2-(AE^2+ED^2)

=cancel(AE^2)+BE^2cancel(-AE^2)-ED^2

=BE^2-ED^2

=(BE+ED)(BE-ED)

=(CE+ED)*BD=CD*BD=RHS