Question

if exterior angle ACD of triangle ABC has the measure 120 degree one of two internal opposite angle of 40 degree find the measure of remaining angle ABC

Answer 1

hey

_______________

the exterior angle of a ∆ triangle is always equal sum of interor opposite angle it is a theorem known as exterior angle theorem

40°+x°=120°

x=120°-40°

x=80°

refer to the attachment for the diagram

hope helped

___________________