docs: fix typo (close #1185)

doc/generic/pgf/pgfmanual-en-tikz-paths.tex

@@ -450,7 +450,7 @@ \subsection{The Circle and Ellipse Operations}
     %
     \begin{key}{/tikz/x radius=\meta{value}}
         Sets the horizontal radius of the circle (which, when this value is
-        different form the vertical radius, is actually an ellipse). The
+        different from the vertical radius, is actually an ellipse). The
         \meta{value} may either be a dimension or a dimensionless number. In
         the latter case, the number is interpreted in the $xy$-coordinate
         system (if the $x$-unit is set to, say, |2cm|, then |x radius=3| will