Question

Using a directrix of y = -2 and a focus of (2, 6), what quadratic function is created?

f(x) = -one eighth (x - 2)2 - 2

f(x) = one sixteenth (x - 2)2 + 2

f(x) = one eighth (x - 2)2 - 2

f(x) = -one sixteenth (x + 2)2 - 2

Answer 1

well the vertex is halfway between the focus and directrix...

the distance distance is twice the foacl length...

so -2 to 6 is a distance of 8... so the focal length is 4

so the vertex is at (2, 2)

that should help

Answer 2

i still dont understna
d

Answer 3

@campbell_st i still dont understand

Answer 4

ok... here is the long alternate method



use the distance formula.

The distance from the focus to a point P on the parabola is equal to the perpendicular distance from P to the directrix...