Find the focus of the parabola \(x = -\frac{1}{12} y^2\).
If you have the equation of a parabola in vertex form x=a(y-k )2+ h, then the vertex is at (k,h) and the focus is (k+1/4a, h).
you have x = -1/12 (y-0)^2 + 0 vertex is thus 0,0 a = -1/12
focus is thus ( 1/(4*-1/12), 0 = -3,0
+37157 
