Find the direction in which a straight line must be drawn through the point `(1," "2)` so that its point of intersection with the line `x" "+" "y" "" "4` may be at a distance of 3 units from this point.

Explanation

Let `y =mx+c` be the line passing through point` (−1,2)`

So, `2 =m(−1)+c`

`=>2=−m+c`

`=>c=m+2`

`∴y=mx+m+2....(1)`

The given line is

`x+y=4....(2)`


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