10.3 notes.notebook
May 19, 2016
Lesson 10.3: Areas of Parallelograms and Trapezoids Objective: Students will calculate the area of parallelograms and trapezoids.
May 19­7:38 AM
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10.3 notes.notebook
May 19, 2016
Key Vocabulary Base of a parallelogram: the length of any one of its sides.
Height of a parallelogram: the perpendicular distance between side whose length is the opposite side. Bases of trapezoid: the lengths of its parallel sides. Height of a trapezoid: the perpendicular distance between the sides whose lengths are the bases.
May 19­7:42 AM
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10.3 notes.notebook
May 19, 2016
Area of a Parallelogram/ Trapezoid
The area of a parallelogram is the product of the base and the height.
A= bh
The area of a trapezoid is half the product of the sum of the bases and the height. A= ½ (b1 + b2) h
May 19­7:50 AM
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10.3 notes.notebook
May 19, 2016
Example 1: Finding the Area of a Parallelogram
The base of a parallelogram is 5 inches. The height is twice the base. Find the area of the parallelogram.
May 19­7:55 AM
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10.3 notes.notebook
May 19, 2016
Example 2: Finding the area of a Trapezoid
The diagram show one of the trapezoids on a quilt design. Find the area of a trapezoid. 4 cm
2.5 cm
9 cm
May 19­8:18 AM
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10.3 notes.notebook
May 19, 2016
Checkpoint
3 m
22 in
5 ft
8.5 m
16 in
6 ft
9 m
13 in
May 19­8:24 AM
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10.3 notes.notebook
May 19, 2016
Example 3: Finding the Unknown
The height of a trapezoid is 6 meters. One of its bases is 8 meters. The area of the trapezoid is 54 square meters. Find the other base. May 19­8:30 AM
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