The area, $a$, of an ellipse can be determined using the formula $a=\pi x y$, where $x$ and $y$ are half the lengths of the largest and smallest diameters of the ellipse.



Which is an equivalent equation solved for $y$?

A$y=a \cdot \pi x$

B$y=a+(\pi x)$

C$y=a-\pi x$

D$y=a \div(\pi x)$