Question

Answer 1

a, Vì Ax//Cz nên \(\widehat{C_1}=\widehat{A_1}\left(đồng.vị\right)\)

b, Vì Ax//Cz nên \(\widehat{C_1}+\widehat{CAx}=180^0\left(trong.cùng.phía\right)\)

c,Vì Cz//By nên \(\widehat{C_2}+\widehat{CBy}=180^0\left(trong.cùng.phía\right)\)

d, Ta có \(\widehat{CAx}+\widehat{CBy}+\widehat{ACB}=\left(\widehat{CAx}+\widehat{C_1}\right)+\left(\widehat{CBy}+\widehat{C_2}\right)=180^0+180^0=360^0\)

e, \(\left\{{}\begin{matrix}AB\perp By\\By//Ax//Cz\end{matrix}\right.\Rightarrow AB\perp Ax;AB\perp Cz\)