a = (1-b (j-y)^2)/x^2 and x!=0
b = (1-a x^2)/(j-y)^2 and j!=y
j = (b y-sqrt(-b (a x^2-1)))/b and b!=0
j = (sqrt(-b (a x^2-1))+b y)/b and b!=0

x = ±sqrt(-b j^2+2 b j y-b y^2+1)/sqrt(a) and a!=0
y = (b j-sqrt(-b (a x^2-1)))/b and b!=0
y = (sqrt(-b (a x^2-1))+b j)/b and b!=0

a*x^2+b*(y-j)^2

solve a 91/4 + 1/10^2 (0 - j)^2=1, a 51/4 + 1/10^2 (10 - j)^2=1