Question

Cho tam giác ABC có: 5.Â=3.B và 2.B=C. Tính A,B,C

Answer 1

Áp dụng tc dtsbn:

\(\dfrac{\widehat{A}}{3}=\dfrac{\widehat{B}}{5};\dfrac{\widehat{B}}{1}=\dfrac{\widehat{C}}{2}\Rightarrow\dfrac{\widehat{A}}{3}=\dfrac{\widehat{B}}{5}=\dfrac{\widehat{C}}{10}=\dfrac{\widehat{A}+\widehat{B}+\widehat{C}}{3+5+10}=\dfrac{180^0}{18}=10^0\\ \Rightarrow\left\{{}\begin{matrix}\widehat{A}=30^0\\\widehat{B}=50^0\\\widehat{C}=100^0\end{matrix}\right.\)