when 2 angles are put next to each other on a straight line with a line going through the middle those two angles always add to 180 since 180 is equal to a straight line.
supplementary angles are 2 angles that together make 180.
out of the options given, all of them except 1 and 7 are equal angles and as a result would not add to 180. if you put angles 1 and 7 on a straight line together, they do, thus the answer is A, aka 1 and 7.
