Question

Prove that the sum of the measures of the interior angles of a triangle is 180°. Be sure to create and name the appropriate geometric figures.

Answer 1

ok , using the parallel axiom is that ok ?

Answer 2

step 1 :-
let l & m two parallel lines

Answer 3

step 2 :-
let ABC a triangle , such that 1,2,3 are the interior angles

Answer 4

step 3:-
all angels (4,5,6,7) are exteriol angels

Answer 5

now lets see the proof :)