# Filldraw square in tikz

I am trying to filldraw a square with sides 7sqrt(7). I am not getting the desired output.

\begin{tikzpicture}
\filldraw(0,0) rectangle (7*\sqrt{7},7*\sqrt{7});
\end{tikzpicture}

• \sqrt{x} is for typesetting the symbol for the square root of x. To perform a calculation, you have to use the pgf function sqrt(x). And to not confuse the coordinate parser (which looks for a ) as the end of the coordinate), any calculations that include parentheses have to be wrapped in {}, to hide them from the coordinate parse. Hence you get the expression ({7*sqrt(7)},{7*sqrt(7)}) shown in hpekristiansen's answer. Jul 11 '21 at 15:51

\documentclass[tikz, border=1cm]{standalone}