 # What are the very basic concepts which the kids should know about the complementary angles?

There are several types of angles available in the world of mathematics about which the kids
need to be very much clear about in the whole process so that they can solve the questions
very easily and a further able to have a good command over the whole world of mathematics.
The supplementary and complementary angles are always defined concerning the addition of
two angles and if the sum of angles will be 180° then they are supplementary which will help in
forming a linear pair as well and on the other hand when the sum of two angles will be 90° they
will be referred to as the complementary angles and they will together form a right angle.

When two lines segments or lines will meet at a common point which is known as vertex the
point of intersection will always lead to the formation of an angle and the rays associated with
the angle will also help in making the initial position and the final position. When the sum of
two angles will be 90° they will be known as complementary angles or in other simple words
whenever two angles will make a right angle then these will be referred to as the
complementary angles. Suppose one angle is X then the other angle will be having the measure
of 90° minus X. Hence, people can very easily utilise these kinds of angles for the trigonometry
ratios where the ratio will complement each other by the 90°. Some of those trigonometry
formulas are explained as follows:

 Sin 90 – A = cos A and cos 90 – A = Sin A
 Tan 90 – A = cot A and cot 90-A = tan A
 Sec 90 -A = cosec A and cosec 90-A = sec A

Here in the above-mentioned formulas, everything will be complementing each other which is
the main reason that kids need to be very much clear about these basic points so that they can
solve further questions very easily.
Following are the basic facts associated with the complementary angles:

 Two right angles can never complement each other
 Two obtuse angles can never complement each other
 Two complementary angles are acute but vice versa is never possible.

There are several ways of differences between the complementary and supplementary angles
with the kids need to be clear about so that there is no confusion element in the whole process
and some of those basic points of differences are explained as follows:

1. The complementary angles will always have some equal to 90° and supplementary
angles we have some equal to 180°.
2. Two angles can complement each other and two angles can even also supplement each
other.
3. Complementary angles are not defined for the linear pair of angles and the
supplementary angles are defined for the linear pair of angles.
4. Complementary angles are only meant for right angles and supplementary angles are
only meant for straight angles.

Hence, being clear about all the above-mentioned points with the help of expert consultancy
provided by Cuemath is very important for the kids so that they can have a good command of
the whole subject very easily.