Find the equation of two straight lines which are parallel to `x+7y+2=0` and at unit distance from the point `(1,-1)dot`

Explanation

Given,lines are parallel to `x+7y+2=0`
at a unit distance from the point `(1,-1)`
using the formula

`d=(xxx x_1+y xxy_1+c)/(sqrt((x_1)^2+(y_1)^2))=1`

`=>(∣1+7(−1)+c∣)/sqrt(1^2
​+7^2)​=1`

`=>(∣c−6∣)=sqrt(50)`

`​=>c=6±sqrt(50)`

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