You can use parallel lines and a transversal if that works for you
did you learn about those things?
ok fill out equivalent angles somewhere so that a b and c form a line
move a to its corresponding angle, and move c to the alternate interior
so c is the intersecting point now?
they want you to show that the angles (a + b + c) = 180
using the parallel line and transversal line, you can arrange angles a b and c to make a line, which is 180 degrees
okay so this now would be a straight proving they equal 180
okay thank you
you can say...
A + C is supplmntary to B , so A + B + C must be 180
yes that makes sense