Question

Giúp mình với ạ

Answer 1

Do \(\widehat{A}=\widehat{D}=60^{0}(so le trong)\)

\(\Rightarrow\)\(AB//CD\)

\(\Rightarrow\)\(x+\widehat{C}=180^0(trong cùng phía) \)

\(\Rightarrow\)\(x+80^0=180^0\)

\(x=100^0\)

Answer 2

+)Vì \(\widehat{A1}\)=\(\widehat{B1}\)(gt)

Mà 2 góc này ở vị trí so le trong 

⇒AB//CD

+Vì AB//CD(cm trên)

⇒\(\widehat{B1}\)+\(\widehat{C1}\)=180⁰

⇒\(\widehat{B1}\)=180⁰-\(\widehat{C1}\)

⇒\(\widehat{B1}\)=180⁰-80⁰

⇒\(\widehat{B1}\)=100⁰

⇒x=100⁰

Answer 3

Ta có: AB//CD

nên \(x+80^0=180^0\)

hay \(x=180^0-80^0=100^0\)