
The third set has three angles that sum to 180° three angles cannot be supplementary. Only those pairs are supplementary angles. Notice the only sets that sum to 180° are the first, fifth, sixth and eighth pairs. Identify the ones that are supplementary: Here are eight sets of angles in degrees. The two angles must either both be right angles, or one must be an acute angle and the other an obtuse angle Only two angles can sum to 180°- three or more angles may sum to 180° or π \pi π radians, but they are not considered supplementary Supplementary angles have two properties: Straight angles - measuring exactly 180° or exactly π \pi π radians Types of supplementary angles Four angle typesĪcute angles - measuring less than 90° or less than π 2 \frac 2 π radians Supplementary angles can also have no common sides or common vertex. Supplementary angles can also share a common vertex but not share a common side. Supplementary angles sharing a common side will form a straight line. In the given figure find the measure of the unknown angle.Supplementary angles are easy to see if they are paired together, sharing a common side. Therefore, the two supplementary angles are 100° and 80°.ĥ. If one angle is 5m, then the other angle is 4m. Two supplementary angles are in the ratio 5 : 4. Therefore, the two supplementary angles are 41.75° and 138.25°.Ĥ. Therefore, we know the value of y = 43.75°, put the value in place of y Since (y – 2)° and (3y + 7)° represent a pair of supplementary angles, then their sum must be equal to 180°. If angles of measures (y – 2)° and (3y + 7)° are a pair of supplementary angles. To find the supplement of (30 + x)°, subtract it from 180° Find the supplement of the angle (30 + x)°. Hence, they are a pair of supplementary angles.Ģ. Verify if 125°, 55° are a pair of supplementary angles?Īdd the given two angles and check if the resultant angle is 180° or not. Then, from the above two equations, we can say, If ∠a and ∠b are two different angles that are supplementary to a third angle ∠c, such that, The supplementary angle theorem states that if two angles are supplementary to the same angle, then the two angles are said to be congruent.


Also, the non-adjacent supplementary angles do not have the line segment or arm. The adjacent supplementary angles have the common line segment or arm with each other. The supplementary angles may be classified as either adjacent or non-adjacent.


The important geometry concepts Lines and Angles are explained on our website with detailed explanations and solved examples. One important thing in supplementary angles is the two angles need not be next to each other. By adding two supplementary angles, they form a straight line and a straight angle. If one angle is 120 degrees then the other angle is 60 degrees in supplementary angles because by adding 120 and 60, we get 180 degrees. Supplementary angles are the angles that are added up to 180 degrees.
