Answer
True
Work Step by Step
The general equation of a conic has the form of $Ax^2+Bxy+Cy^2+Dx+Ey+F=0(1)$
(a) When $B^2-4AC=0$, then a conic defines a parabola.
(b) When $B^2-4AC \lt 0$, then a conic defines an ellipse and $A\ne C$
(c) When $B^2-4AC \lt 0$, then a conic defines a circle and $A=C$
(d) When $B^2-4AC \gt 0$, then a conic defines a hyperbola.
We have: $A=a,B=0,C=6$.
Plug these values in Equation (1) to obtain: $B^2-4AC=(0)^2-4(a)(6)=-24a$
The conic will represent an ellipse when $-24a \lt 0 \\ -a \lt 0 \\ a \gt 0$
Therefore, the statement is True.