Complementary vs Supplementary Angles

Complementary vs Supplementary Angles - How it Works - Video

Types of Angles

Types of Angles:

Here we have the 4 major type of angles: acute angles, right angles, obtuse angles, and straight lines. There are more, but these are the ones that deal with complementary and supplementary angles specially right angles and straight lines.

Complementary Angles

Complementary Angles:

Complementary Angles are 2 angles that add up 90°. If we have a right angle already, we could split the right angle in any which way and those two adjacent angles will be complementary.

Once the angles are not adjacent then, we have to add them up and see which pair adds up to 90°. In this it is 38° and 52°.

Complementary Angles:

Here we put the two nonadjacent angles and form a right angle. <BAC and <CAD form the right angle since the sum is 90°.

Supplementary Angles

Supplementary Angles:

Supplementary Angles are 2 angles that add up 180°. If we have a straight line already, we could split the straight line in any which way and those two adjacent angles will be supplementary.

Once the angles are not adjacent then, we have to add them up and see which pair adds up to 180°. In this it is 118° and 62°.

Supplementary Angles:

Here we kept the two nonadjacent angles separate to show the difference between linear pair and supplementary.

On the left <ABC and <CBD form the straight line and form a linear pair because they are also adjacent angles.

On the right <E and <f are supplementary but do form a linear pair because they are not adjacent angles.

So all linear pairs are supplementary but not all supplementary angles are linear pairs.

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