Find the equation of the ellipse with foci (1, 0) and (7, 0), which has a vertex at the origin?
I came up with the equation
(((x-4)^2)/16)+((y^2)/15)=1

Question

I came up with the equation 
(((x-4)^2)/16)+((y^2)/15)=1

? · Answer

Centre is midway between foci at (4,0)
a = 4
c = 3
9 = 16-b^2
b^2 = 7
(x-4)^2/16+y^2/7 = 1

Find the equation of the ellipse with foci (1, 0) and (7, 0), which has a vertex at the origin?