Answer:
x^2/4 +y^2/9 = 1
Explanation:
It is reasonable to start with the form ...
(x/a)^2 +(y/b)^2 = 1
where "a" is the length of the semi-axis in the x-direction (2), and "b" is the length of the semi-axis in the y-direction (3).
Then you have ...
(x/2)^2 +(y/3)^2 = 1
The preferred form of this has the denominators multiplied out:
x^2/4 +y^2/9 = 1