If the focus of a parabola is (-2,1) and the directrix has the equation `x+y=3` then its vertex is a. (0,3) b. (-1,1/2) c. (-1,2) d. (2,-1)

Explanation

`x+y=3 and m=−1`

`(−2,1)`
`m=1`

`y−1=1(x+2)`

`y−1=x+2`

`x−y+3=0`

`x−y+3=0`

`x+y−3=0`

`2x=0`
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