ANGLED\[\DELTA \,ADC,\] \[AD=\sqrt{{{(5.1)}^{2}}-{{2.3}^{2}}}=4.55\,m\] \[\THEREFORE \] Area of\[\Delta \,ABC=2.3\times 4.55=10.47\,\TEXT{sq}\text{.}\,\text{m}\text{.}\]