Question

Giải giúp mình 2 bài này nha. Cảm ơn

Answer 1

Ta có:

\(\widehat{A}+\widehat{B}+\widehat{C}+\widehat{D}=360^o.\)

Mà \(\widehat{B}=\widehat{A}+10^o.\\ \widehat{C}=\widehat{B}+10^o=\widehat{A}+10^o+10^o=\widehat{A}+20^o.\\ \widehat{D}=\widehat{C}+10^o=\widehat{A}+20^o+10^o=\widehat{A}+30^o.\)

\(\Rightarrow\widehat{A}+\widehat{A}+10^o+\widehat{A}+20^o+\widehat{A}+30^o=360^o.\\ \Leftrightarrow4\widehat{A}=300^o.\\ \Leftrightarrow\widehat{A}=75^o.\\ \Rightarrow\widehat{B}=85^o.\\ \widehat{C}=95^o.\\ \widehat{D}=105^o.\)