In `DeltaABC` if `(c+a)/(12)=(a+b)/(14)=(b+c)/(18)`, then find the value of `(7r_(1)-r_(2))/(11r)` is.

Answer

0

Explanation

`(c+a)/12=(a+b)/14=(b+c)/18=s/11`
`B=c=18/11s`
`implies2s-a=18/11s`
`impliess-a=7/11s`
`r_(1)=(Delta)/(s-a)=(11Delta)/(7s)=11/7r`
`a+c=(12s)/11`
`s-b=s/11`
`r_(2)=(Delta)/(s-b)=(11Delta)/s=11r`
`implies(7r_(1)-r_(2))/11=(11r-11r)/(11r)=0`