% https://alfurka.github.io/quick-tikz/
\def \recA {(-4,-1) rectangle ++(6,3)}
\def \lineA {(4,5) -- (-5,-4)}

\begin{tikzpicture}[background rectangle/.style={fill=white}, show background rectangle]
  % Axis
  \draw (-5,0) -- (5,0);
  \draw (0,-5) -- (0,5);
  \draw[step=1,gray,very thin] (-4.8,-4.8) grid (4.8,4.8);

  % Main shapes
  \draw[blue] \recA;
  \draw[red] \lineA;

  % Intersection
  \begin{scope}
    \clip \recA;
    \draw[pattern=north west lines] \lineA -- (-5,5) -- cycle;
  \end{scope}
\end{tikzpicture}