\({S_{ABCD}} = \left| {\left[ {\overrightarrow {AB} ,\overrightarrow {AD} } \right]} \right|\)              

\({S_{ABCD}} = \dfrac{1}{2}\left| {\left[ {\overrightarrow {AB} ,\overrightarrow {AD} } \right]} \right|\)

\({S_{ABCD}} = 2\left| {\left[ {\overrightarrow {AB} ,\overrightarrow {AD} } \right]} \right|\)

\({S_{ABCD}} = 4\left| {\left[ {\overrightarrow {AB} ,\overrightarrow {AD} } \right]} \right|\)