PLEASE HELP I see the correct answer but I have to fine out how I found it

i used to know how to do this in 7th but i forget easily

step-by-step explanation:

i get you, what you should do is think of the positive things that would come out of it. it will make yours parents proud and raise your grade. you should always try and if you can't focus tell the teacher.

180°

step-by-step explanation:

sum of equilateral triangle=180°

< n=60°

< m=120°°[angle supplementary of equilateral angle]

< m+< r+< x=360°(sum of exterior angle of triangle)