tứ giác ABCD có
\(\widehat{A}+\widehat{B}+\widehat{C}+\widehat{D}=360^0\left(tổng-4-góc-của-tứ-giác\right)\)
\(\rightarrow\widehat{D}=180-\left(\widehat{A}+\widehat{C}+\widehat{B}\right)\)
\(\rightarrow\widehat{D}=360-\left(36+156+49\right)=360-241\)
\(\rightarrow\widehat{D}=119^0\)