

They can be right next to each other, but they dont have to be. So notice that for a supplementary and for complementary you can't say that five angles are complementary but we're always talking about pairs or two's. Two angles that add up to 90 degrees are called complementary angles. Now, a supplementary pair could be angle 4 and angle 5 which are adjacent and they are linear. So complementary angles could be angles 1 and 2. Here we have five angles 1, 2, 3, 4 and 5 and we're told that this angle 3 is 90 degrees, now one thing that you can assume is that 1, 2 and 3 are all linear, so if you add up 1, 2 and 3 it would be 180 degrees, which means that 1 and 2 must also sum to 90 degrees so I could label this as a right-angle. Let's look at a specific example where you might be asked to identify supplementary angles and complementary angles.

The same is true for complementary angles. 2 Complementary and Supplementary Angles: Complementary Angles Two angles that add up to 90 degrees. But I could also say if we had some angle here that we said three and let's say 3 was equal to 60 degrees and I had some other angle over here, let's say angle four was equal to 120 degrees, I could say that these two angles three and four are supplementary because they sum to 180 degrees. So supplementary angles could be adjacent so if I had angles one and two those two would be supplementary. And I noted here that these do not have to be adjacent. Supplementary angles are two angles whose measures sum to a 180 degrees and complementary are the sum have to add up to 90 degrees. The letter ‘c’ in complementary comes before the letter ‘s’ in supplementary, just like 90° comes before 180°.Two concepts that are related but not the same are supplementary angles and complementary angles.True or False: If two angles are complementary, they are both. True or False: If segment XY is perpendicular to segment XZ, then angle YXZ is acute. True or False: If two angles are supplementary and one is obtuse, the other one is acute. Supplementary angles form a straight line and have a sum of 180 degrees. I know it's a little hard to remember sometimes. True or False: If two adjacent angles form a linear pair, they must be supplementary angles. Complementary angles form a right angle (L shape) and have a sum of 90 degrees. Hence when two supplementary angles are put together they form a ‘straight’ angle. And when you have two angles that add up to 180 degrees, we call them supplementary.

