Question 932627
 Standard Form of an Equation of an Ellipse is {{{(x-h)^2/a^2 + (y-k)^2/b^2 = 1 }}} 
where Pt(h,k) is the center. (a variable positioned to correspond with major axis)
 a and b  are the respective vertices distances from center.
 The foci distances from center:   c = ±{{{sqrt(a^2-b^2)}}} where  a > b
.......
vertices at (5,1) and (-5,1)
{{{(x)^2/5^2 + (y-1)^2/b^2 = 1 }}} 
2 = ±{{{sqrt(25-b^2)}}}
4 = 25 - b^2
b^2 = 21
.......
{{{(x)^2/25 + (y-1)^2/21 = 1 }}}
.......
{{{drawing(300,300,    -10,10,-10,10,  arc(0,1,10, 2sqrt(21)),   
 grid(1),
circle(0, 1,0.4),
circle(0, 1+sqrt(21),0.4),
circle(-5,1,0.4),
graph( 300, 300, -10,10,-10,10,0,1))}}}