You can calculate supplementary angles by subtracting the specified angle from 180 degrees. Note that, when two adjacent supplementary angles are put together, they form a straight line. Hence, they are supplementary angles but not adjacent. But when added up, that is 130° + 50° = 180°, their sum comes as 180°. Here, ∠ ABC and ∠ PQR are non-adjacent angles as they neither have a common nor a common arm. Put simply, two supplementary angles that are not adjacent are said to be non-adjacent supplementary angles. Hence, these two angles can be called adjacent supplementary angles. These two angles add up to 180 degrees, that is ∠ BOA + ∠ AOC = 180°.

Here ∠ BOA and ∠ AOC are adjacent angles as they have a common vertex, O, and a °common arm OA. Two supplementary angles that have a common vertex and a common arm are said to be adjacent supplementary angles. Each of these types of supplementary angles is explained below. Types of Supplementary AnglesĪdjacent and non-adjacent supplementary angles are the two types of supplementary angles. However, linear pairs are always supplementary. So, remember that supplementary angles are not necessarily linear pairs. Supplementary angles do not have to be adjacent, but linear pairs must be adjacent to form a straight line. One of the most asked questions is whether all supplementary angles form linear pairs? Hence, any two angles can be supplementary angles, if their sum is equivalent to 180 °. But also note that even if two angles are supplementary to each other, they do not have to be next to each other. When two supplementary angles are joined together, they form a straight line and a straight angle. In a supplementary angle if one angle is 90°, then the other angle will also be 90°.The supplementary angles do not have to be on the same line, they can be on different lines, but should measure 180°.The “S’ in supplementary angles stand for Straight line, this means that they form 180°.Any two angles are said to be supplementary angles when their sums add up to 180°.Supplementary angles all share the same properties: Let’s try to find the supplementary angle measurement for each measured angle. Now when you look at the above examples you will find that there will always be an obtuse angle (150°, 130°, 96°, 120°) added with an acute angle (60°, 90°, 40°, 84°) or there will be a sum of two right angles (90°, 90°). Let’s look at some examples of supplementary angles to get a better understanding: As you go through, you will explore a world of supplementary angles with important applications in solving various geometric problems.

Definition supplementary angle