%flow.fg1
\flowchart{\flowstart\flowinput{$a,b,c$}
\flowcompute{$d={b^2-4ac}$}
\flowcompute{$\displaystyle 
x_1={b+\sqrt d\over-2a\strut}$
% \strut inhibits touching of the two 
% formulae in a vertical arrangement
$\displaystyle x_2={b-\sqrt d\over-2a}$}
\flowoutput{$x_1,x_2$}\flowend}