Raymond B. answered 10/10/21
Math, microeconomics or criminal justice
it's a left ward opening parabola because the focus is to
the left of the directrix
general form is x= a(y-k)^2+ h
where (h,k) is the vertex, half way between focus and directrix
axis of symmetry is y = 2, where h=2, k=-5
x=a(y+5)^2 + 2
plug in another point on the parabola to solve for "a"
distance from focus to a point on the parabola = distance from that point to the directrix. Go up vertically from (2,-5) to (-2,3)
(-2,3) is a point on the parabola because it is 8 units above the focus and 8 units to the left from the directrix
x = a(y+5)^2 +2
-2 = a(3+5)^2 +2
64a = -4
a =-4/64 = -1/16
the parabola equation is:
x = (-1/16)(y+5)^2 + 2
or 16x = -(y+5)^2 + 32
or 16x = -y^2 - 10y + 7