Find equation of the line perpendicular to the line `x" "" "7y" "+" "5" "=" "0` and having x intercept 3.

Explanation

Let equation of a line perpendicular to line `x-7y+5=0` is ,
`7x-y+lambda=0` ………`(1)`
The `x`-intercept of this line is `3`,
i.e, this line passes through `(3,0)`.
`:. 7(3)+0+lambda=0`
`implies lambda=-21`
From equation `(1)`,
required equation is, `7x+y-21=0`