add up all the inside angels, you'll get 122, subtract that from the total area of the triangle which is 180. you will have 58 for your missong inside triangle. the outside line makes 180 with the angel we just found, so subtract 58 from 180 and you get 122. check out Khan Academy for help.
She is not correct because “value of expressions” mean the result which for this it is 16-13 =3 and she is wrong. please mark me brainly! Hope this helps! :D