Find the focus directrix and focal diameter of the parabola
     Find the focus, directrix, and focal diameter of the parabola. x - 7y^2 = 0  focus (x - y) = ()  directrix  focal diameter   
  
  Solution
Solution:
y^2 = 4px , where the focus is (p, 0) and the directrix is x = - p
 7y^2 = x
 y^2 = (1/7)x
 4p = 1/7
 p = 1/28
 focus at (1/28 , 0)
x = -1/28 => directrix
 
 Focal diameter = 4p = |1/7| = 1/7

