Please solve q 46 ?

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1 Answer
CW
May 10, 2018

#7/9#

Explanation:

enter image source here
let #angleBAC=x, => angleBCD=x#,
let #angleACD=y, => angleBDC=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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