\( \definecolor{colordef}{RGB}{249,49,84} \definecolor{colorprop}{RGB}{18,102,241} \)
A polygon has an area of 4 square units. It is transformed by the matrix \(\mathbf{C} = \begin{pmatrix} 1 & 3 \\ 2 & 4 \end{pmatrix}\).
Find the area of the image of the polygon.
\(\text{Area}(S')=\)
square units