If focus and directrix of a parabola are (3,-4) and x+y+7=0 then its length of latuusrectum is?

Answer 1

The latus rectum's length is 2 times the distance from the focus to the directrix.

Now recall the point-to-line distance formula, and you get

|3*1-4*1+7|/√(1^2+1^2)

Answer 2

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