Question 859358
A Complementary angles add up to 90. Each of them has to be less than 90° (acute) as otherwise they would exceed 90, right?


B Supplementary angles add up to 180°. They don't have to be the same size. When one is smaller than 90°, the other one is larger. So x is sometimes acute.


C Never... this is basically a definition.


D Sometimes. Complementary and supplementary angles don't have to be adjacent.


E Sometimes. Vertical angles are equal, so this situation is only possible when x and y are right angles because then they are supplementary and are vertical.