Question

dertemine os angulos indicados pelas letras

Answer 1

A) 90+90+x+120=360
    300+x=360
      x=60º

Answer 2

a)  
90+90+x+120=360
x=360-300
x=60

b) 120+2x=180
2x=180-120
x= 60/2
x= 30°