Respuesta :
Answer: 12
Step-by-step explanation:
since it’s isosceles, the bottom two angles are equal so just subtract 156 from 180 and then divide that by 2.
Whenever you see an isosceles triangle, you should know that the bottom two angles are the half of the top angle subtracted from 180. So, 180-156=24 —> 24/2= 12°