Find the vertex, focus, and directrix of the parabola given by the equation (y+2)^2=-4(x-1).
a.) vertex: (2,-1); focus: (0,-1); directrix: x= -1
b.) vertex: (-1,2); focus: (0,2); directrix: x= -2
c.) vertex: (1,-2); focus: (0,-2); directrix: x=2
d.) vertex: (-2,1); focus: (0,1); directrix: x= 1

Question

Find the vertex, focus, and directrix of the parabola given by the equation (y+2)^2=-4(x-1).
a.) vertex: (2,-1); focus: (0,-1); directrix: x= -1
b.) vertex: (-1,2); focus: (0,2); directrix: x= -2
c.) vertex: (1,-2); focus: (0,-2); directrix: x=2
d.) vertex: (-2,1); focus: (0,1); directrix: x= 1

anonymous · Answer

The vertex is (1,-2) . This can be read from the equation.
There is only one choice that statisfies that