Question

Mn giúp mk với 

Answer 1

a) Ta có: a⊥m,b⊥m

=> a//b

b) Ta có: a//b

\(\Rightarrow\widehat{D_1}=\widehat{xBD}=60^0\)(so le trong)

\(\Rightarrow\widehat{D_1}=\widehat{D_2}=60^0\)(đối đỉnh)

c) Ta có: a//b

\(\Rightarrow\widehat{ABD}=\widehat{CDE}\)(đồng vị)

\(\Rightarrow\dfrac{1}{2}\widehat{ABD}=\dfrac{1}{2}\widehat{CDE}\)

\(\Rightarrow\widehat{DBt}=\widehat{EDy}\)

Mà 2 góc này đồng vị

=> Bt//Dy