Hi,
ellipse with foci points (5,4) and (-3,4) and the major axis is 10 units long.
foci are each 4 from Center..center is (1,4)
Standard Form of an Equation of an Ellipse is
where Pt(h,k) is the center and a and b are the respective vertices distances from center
and 4(distance of foci from Center) = sqrt(a^2-b^2) = sqrt(100-b^2), b = sqrt(84)