We see from the square marking that both angles add up to be 90 degrees. Knowing this, we can do 90-43 so that we know the total measure of the top angle. Doing this, we know that the top angle equals 47. We can write this out as 5x-8=47, because they are the same thing. We add 8 to both sides, and get 5x=55. Now we divide both sides by 5 and get x=11. Now we have x, so let's decide if the angle pair is complementary or supplementary. Well, supplementary means the angles add up to be 180 degrees, and complementary means they add up to 90 degrees. We already said that the angle pair added up to 90 degrees, so the angle pair is complementary.
