properties of trapezoids

1. PROPERTIES OF
TRAPEZOIDS
Lesson 5.4

2. Objectives: • Identify the parts of a
trapezoid;
• Recognize the properties of a
trapezoid; and,
• Differentiate the properties
between a trapezoid and a
parallelogram.

4. Draw the
following:
• Quadrilateral ABCD and AB || CD.
• Quadrilateral RSTW and RW || ST.
• Quadrilateral JKLM, no sides are
equal.

5. Questions: • Which of the given quadrilaterals
is/are trapezoid?
• What do you call the parallel sides
of a trapezoid?
• What do you call the nonparallel
sides of a trapezoid?
• What angle is being formed by the
legs and one of the bases?
• What is the sum of a pair of base
angles?

6. Example:
In a trapezoid
PQRS,
PQ || RS.
• Name the bases, the legs, and
both pairs of base angles.
• Find the measure of angle S
and Q.

7. Isosceles
Trapezoid
• If the legs of a trapezoid are equal, then
the trapezoid is called an isosceles
trapezoid.
Properties of Isosceles Trapezoid
• The lower and upper base angles are
equal.
• The diagonals of an isosceles trapezoid
are equal.

8. Summary of Properties of Diagonals
of Special Quadrilaterals
Special
Quadrilaterals
Diagonals are always
Diagonals
always Bisect
Equal Perpendicular Each Other VertexAngles
Parallelogram
Rectangle
Rhombus
Square
Trapezoid
Isosceles
Trapezoid

9. Class
Activity
Answer
ACTIVITY A, items 1 – 4
ACTIVITY B, items 1 – 2
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