Find the equation of an ellipse whose axes lie along coordinates axes and which passes through (4, 3) and (- 1, 4).
Given that we need to find the equation of the ellipse passing through the points (4,3) and (- 1,4).
Let us assume the equation of the ellipse as (a2>b2). - - - - (1)
Substituting the point (4,3) in (1) we get
⇒
⇒
⇒
⇒ 16b2 + 9a2 = a2 b2 ..... - - (2)
Substituting the point (- 1,4) in (1) we get
⇒
⇒
⇒
⇒ b2 + 16a2 = a2b2 ..... - - (3)
(3)×16 - (2)
⇒ (16b2 + 256a2) - (9a2 + 16b2) = (16a2b2 - a2b2)
⇒ 247a2 = 15a2b2
⇒ 15b2 = 247
⇒
From (3)
⇒
⇒
⇒
⇒
The equation of the ellipse is
⇒
⇒
⇒ 7x2 + 15y2 = 247
∴ The equation of the ellipse is 7x2 + 15y2 = 247.