Question 817900
  <pre><font face = "Tohoma" size = 3 color = "indigo"><b> 
Hi,
27x^2+9y^2=81
{{{x^2/3 + y^2/9 = 1}}} C(0,0) a = 3  and b = sqrt(3)
± sqrt(9-3) = ± sqrt(6)  F(0,{{{sqrt(6)}}}) and (0,  -{{{sqrt(6)}}})
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 {{{green(major axis)}}}
 a and b  are the respective vertices distances from center
 and ±{{{sqrt(a^2-b^2)}}}are the foci distances from center: a > b

{{{drawing(300,300,   -6, 6, -6, 6, grid(1),arc(0,0,2sqrt(3),6),  
circle(0, 0,0.2),
circle(0, 3,0.2),
circle(0, -3,0.2),
circle(0, sqrt(6),0.2),
circle(0, -sqrt(6),0.2),
graph( 300, 300, -6, 6, -6, 6))}}}