Respuesta :

701331
Answer: X = 109, 109-20=89
fatemehkorea

Answer:

∠B = 89°

Step-by-step explanation:

  • supplementary angles are two angles whose sum is 180°

∠A + ∠B = 180°

x - 18 + x - 20 = 180

x + x = 180 + 18 + 20

2x = 218

x = 218/2

x = 109

∠B = 109 - 20 = 89

∠B = 89°