is this a circle or an ellispe
4(x-2)^2 + 4(y-4)^2=36
It is a circle because the coeffients of the x terms and the y terms are the same. Note that it could be rewritten in the standard circle equation form:
[(x-2)/3]^2 + [(y-4)/3]^2 = 1
The radius of the circle is 3 and the center is at (x,y) = (2,4).