Question 876615
4x^2-y^2-16x-4y-4=0 
 4x^2-y^2-16x-4y=4 
4(x-2)^2 -(y+12)^2 = 4 +16 -4 = 16
4(x-2)^2 -(y+12)^2 = 16
(x-2)^2/4 -(y+12)^2/16 = 1