1. Day 106 – Introduction to quadrilaterals

2. Introduction
Figure out these, most of our houses or rooms in our houses are designed in a figure with 4 sides, other things such as screens, laptops, windows, doors, game pitches, writing papers among others, have four corners and four sides. I hope this could be one of the most utilized geometric figures in the world. Therefore, it's worth knowing what they are and the forms that they take. In this lessons, we are going to define and identify quadrilaterals.

3. Vocabulary Quadrilaterals
These are 4 sided figures. The sum of interior angles of a quadrilaterals 180°.

4. Rectangle This is a four-sided figure where opposite sides are equal and parallel. All interior angles are equal to 90°. Square This is a four-sided figure where opposite sides parallel and all sides are equal. All interior angles are equal to 90°. Due to these features, it is also called a regular quadrilateral.
Rectangle
Square

5. Parallelogram This is a four-sided figure where opposite sides are equal and parallel. The opposite angles are equal, and adjacent angles add up to 180° Rhombus This is a four sided figure where opposite sides are parallel, and all sides are equal. The opposite angles are equal, and adjacent angles add up to 180°. Its diagonals are perpendicular.
Rhombus
Parallelogram

6. Trapezoid This is a four sided figure where two sides are parallel
Trapezoid This is a four sided figure where two sides are parallel. Kite It is a four sided figure where the diagonals are not equal but perpendicular to each other.

7. Example Identify the quadrilateral where the diagonals are perpendicular. Solution By the properties of the quadrilateral, we find that the rhombus and the kite are the only figures satisfying the above conditions.

8. homework
Identify the following figures
(i)
(ii)
(iii)

9. Answers to homework
Trapezoid (i) and (ii) Rectangle (iii)

10. THE END