# How do you solve Y = (x - 5)² - 9?

$x = 5 \pm \sqrt{Y + 9}$
You have the solution of $Y$ in terms of $x$, to reverse this and solve for $x$ in terms of $Y$ we have:
$Y = {\left(x - 5\right)}^{2} - 9$ => ${\left(x - 5\right)}^{2} = Y + 9$
$x = 5 \pm \sqrt{Y + 9}$