Theo đề ra, ta có:
\(DK=\dfrac{1}{3}BC\)
\(ME=\dfrac{1}{3}CA\)
\(HN=\dfrac{1}{3}AB\)
\(\Rightarrow S_{\Delta ADK}=\dfrac{1}{9}S_{\Delta ABC}=\dfrac{1}{9}\times270=30cm^2\)
Tương tự, ta có:
\(S_{\Delta AHN}=\dfrac{1}{9}S_{\Delta ABC}=\dfrac{1}{9}\times270=30cm^2\)
\(\Rightarrow S_{\Delta BME}=30cm^2\)
\(S_{DEMNKH}=S_{ABC}-3\times S_{AKD}=180cm^2\)