# \polyprint doesn't work properly with brackets?

An MWE:

\documentclass{standalone}
\usepackage{polynom}
\begin{document}

I think the result should be 70x-71 but the result is 70x+1. I think the +1 is the result of 5*(-7) + 4*9 (the correct expression is 5*(-7) - 4*9 of course).
• Note that \polyadd\polya{5(6x-7)}{4(10x-9)} gives the correct result. – user121799 Nov 30 '17 at 18:36
• Workaround: 5(6x-7)+(-4)(9-10x) – Heiko Oberdiek Nov 30 '17 at 19:21