This document discusses properties and types of quadrilaterals:
- A quadrilateral is a polygon with four sides. Properties include four sides, two-dimensional shape, closed figure with straight sides, and interior angles summing to 360 degrees.
- Types of quadrilaterals include: parallelograms, rectangles, rhombuses, squares, trapezoids, and kites. Each type has unique defining geometric properties.
- Examples show how to calculate unknown angle measures in different quadrilaterals using the property that interior angles sum to 360 degrees. Students are assigned to create a Venn diagram comparing types of quadrilaterals.
1. Good morning everyone! Before we
will start our discussion for this day,
let’s have a prayer first. I request
everyone to please stand up.
2.
3.
4. A Quadrilateral is a polygon with four sides.
Quadrilateral just means “four sides”. (quad means
four, lateral means side).
A Quadrilateral has four-sides, 2-dimensional (a
flat shape), closed (the lines join up), and
has straight sides.
7. 1. Parallelogram
A Parallelogram is a
quadrilateral with two pairs
of opposite sides parallel to
each other. Opposite angles
are also equal.
8. 2. Rectangle
A Rectangle is a
four-sided shape where
every angle is a right
angle (90°). The opposite
sides are also parallel
and equal in length.
9. 3. Rhombus
A Rhombus is a four-sided shape where all sides have
equal length. The opposite sides are also parallel and opposite
angles are equal. The diagonals bisect each other and meet in
the middle at a right angle.
10. 4. Square
A Square has equal
sides and all angles are
right angles or measures
90°. The opposite sides
are also parallel.
11. 5. Trapezoid
A Trapezoid is a quadrilateral with exactly one
pair of opposite sides parallel to each other called the
bases. The other non-parallel sides are called the legs.
12. It is called an Isosceles Trapezoid if the
sides that aren't parallel are equal in length and
both angles coming from a parallel side are equal.
13. 6. Kite
A Kite has two pairs of sides.
Each pair is made up of adjacent sides
that are equal in length. The angles are
equal where the pairs meet. Diagonals
meet at a right angle, and one diagonal
bisects the other.
17. Assignment:
Using the Venn diagram, present the
relationship of the types of Quadrilaterals.
Write it in a one whole sheet of
intermediate paper and pass it next
meeting.
20. 1) 102° + 90° + 90° + A = 360°
282° + A = 360°
A = 360° - 282°
A = 7𝟖°
102°
A
Examples: Angles in Quadrilateral
Solutions:
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21. 2) 2A + 2B= 360°
B = (90° + 26°)
B = 116°
2A + 2(116°) = 360°
2A + 232° = 360°
2A = 360° - 232°
2A= 128°
A =
128°
2
A = 64°
Examples: Angles in Quadrilateral
Solutions:
A
B
26°
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22. 1) A = 84°
A + B + 90° + 120° = 360°
84° + B + 90° + 120° = 360°
B + 294° = 360°
B = 360° - 294°
B = 6𝟔°
Exercise 1: Angles in Quadrilateral
Solutions:
120°
84°
A
B
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23. A
C
B
68°
88°
62°
2) 88° + B + 68° + 62° = 360°
B + 218° = 360°
B = 360° - 218°
B = 142°
Exercise 1: Angles in Quadrilateral
Solutions:
24. A + 68° + 62° = 180°
A + 130° = 180°
A = 180° - 130°
A = 5𝟎°
Exercise 1: Angles in Quadrilateral
Solutions:
C + 88° + 62° = 180°
C + 150° = 180°
C = 180° - 150°
C = 3𝟎°A
C
B
68°
88°
62°
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