Answer:
Major axis length = 10
Step-by-step explanation:
Given:
The equation given is:

The above equation represents a standard ellipse of the form:

If
then 'a' is the semi-major axis length and 'b' is the semi-minor axis length.
If
, then 'a' is the semi-minor axis length and 'b' is the semi-major axis length.
On comparing the given equation with the standard form, we get:

Here, b > a as 5 > 4. So, the length of major axis is twice the length of 'b' and is equal to:
Major axis length = 