Please solve q 46 ?

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1 Answer
CW
May 10, 2018

7/979

Explanation:

enter image source here
let angleBAC=x, => angleBCD=x∠BAC=x,⇒∠BCD=x,
let angleACD=y, => angleBDC=x+y∠ACD=y,⇒∠BDC=x+y,
=> DeltaBDC and DeltaBCA are similar,
=> (AC)/(BC)=(CD)/(BD),
=> (AC)/12=6/9, => AC=8, cm
similarly, (AB)/(AC)=(CB)/(CD),
=> (AB)/8=12/6, => AB=16 cm
=> AD=AB-DB=16-9=7 cm
perimeter of ADC=p_1=7+6+8=21 cm
perimeter of BDC=p_2=9+6+12=27 cm

=> (p_1)/(p_2)=21/27=7/9

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