How to put an angle on a specific point? [closed]

1
2
\begin{pspicture}(0,0)(6,5)¬
\pstTriangle(0,0){a}(4;50){b}(4,0){c}¬
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

LaTeX

Compile Error

1. Check the configured compile mode in settings

2. Check the LaTeX log file: