Which is the equation of an ellipse centered at the origin with foci on y-axis, major axis of length 20 and minor axis of length 18?

Option C

x^2/81+y^2/100=1

Centered at the origin means (h,k) =(0,0)

Length of major axis, 2a = 20

That gives, a =10

Length of minor axis, 2b =18

That gives, b=9

And since focii is on the y axis, so its a vertical ellipse of the form

Substituting the values of a and b, we will get

b

step-by-step explanation:

step-by-step explanation:

when the line is solid:

when the line is dashed:

this > inequality sign means:

this < inequality sign means:

this > inequality sign means:

this < inequality sign means:

about the problem:

srry i'm not done ! i'll