For example, $x+y=x\times y$ is easy to express as $y=\frac{x}{x-1}$, how about $x-y=\frac{x}{y}$?
I tried multiply both sides by $y$ and become
$y^2-xy+x=0$
but up to this step I don't know how to continue, can anyone help?
For example, $x+y=x\times y$ is easy to express as $y=\frac{x}{x-1}$, how about $x-y=\frac{x}{y}$?
I tried multiply both sides by $y$ and become
$y^2-xy+x=0$
but up to this step I don't know how to continue, can anyone help?
On
It cannot be done, because, as you correctly noticed, the expression (if $y\neq 0$) is equivalent to the expression
$$y^2 - xy + x = 0$$
This expression can have, for a fixed value of $x$, two solutions, one solution, or even no real solution.
For example, if $x=1$, then there is no real value of $y$ that satisfies the equality, but if $x=-1$, there are two such values of $y$.
Solve for y in quadratic equation
$y^2-xy+x=0$
Using quadratic formula.