What is the length of BD?

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Answer 1 · 2017-09-01T10:20:16

The length is $B D = 36 c m$ $BD=36cm$

Let the mid-point of $B C$ $BC$ be $= E$ $=E$

Let the mid-point of $C D$ $CD$ be $= F$ $=F$

Then,

$A G = \frac{2}{3} A E$ $AG=2/3AE$ and $AG'=2/3AF$

As $G$ and $G'$ divide $AE$ and $AF$ in the same ratio

The lines $GG'$ and $BD$ are parallel

We apply Thales' Theorem

$GG'=2/3EF$

$EF=3/2*12=18cm$

$BD=2*EF=2*18=36cm$