Question

pfv, eu preciso disso pra amanhã

Answer 1

Resposta:

β+α+80 =180  ==>β =100-α   (i)

2α-20=β  (ii)

(i)=(ii)

100-α =  2α-20

120= 3α    

==>α  = 40°

Usando (ii)  

==> β =100-40 =60°