Question

the side BA and DC of quadrilateral ABCD are produced as shown in figure prove that x+y = a+b

Answer 1

Answer:

b  

∘

+∠DAB=180  

∘

 

⟹∠DAB=180  

∘

−b  

∘

.......(i)

i hope the answer in right

a  

∘

+∠BCD=180  

∘

 

⟹∠BCD=180  

∘

−a  

∘

.......(ii)

and ∠A+∠B+∠C+∠D=360  

∘

 

⟹180−b+x+180−a+y=360

⟹x+y=360−180+b−180+a

∴x+y=a+b