144. Solve the equation in rational numbers:

$$
a x+b y+c=x y
$$

## A modern Indian problem.
144. The equation $a x+b y+c=x y$ can be transformed as: $c=x y-a x-b y$.

Adding $a b$ to both sides:

$$
a b+c=x y-a x-b y+a b
$$

or

$$
a b+c=y(x-b)-a(x-b)=(x-b)(y-a)
$$

Bhaskara concludes that in the case of rational $x$ and $y$, one should take:

$$
\begin{gathered}
x=b+n \\
y=a+\frac{a b+c}{n}
\end{gathered}
$$