| Lesson 3: Area of a Trapezoid | Lesson Component
| Description of Component For This Lesson
| | Lesson Opening
(10 minutes)
Introduction of New Material
(5 minutes)
| Objective: To calculate the area of a trapezoid. SWBAT:
(1) identify a trapezoid and it’s component parts
(2) locate or construct a trapezoid height
(3) calculate the area and perimeter of a trapezoid
Do Now: Refresh simplifying radical expressions / polynomial distribution
Simplify 2√ 3 ∙ 5√ 3
Factor 3y2 – 5y - 2
Homework posted on board as students enter
[HW] Pg. 436, Nos. 1-12
(1) Mini-lesson
I will describe the characteristics of a trapezoid (exactly one pair of opposite sides – the bases – are parallel, interior angles still total 360), highlighting the case of the isosceles trapezoid. I will demonstrate how to identify each base, the median and either identify or construct the height. I will demonstrate the proof Area = mh. I will review the proper formula for calculating the area of a trapezoid using the median or by Area Addition postulate. I will identify all the variables (Area A, height h, base b1 and b2, median m).
 A = ½h (b1 + b2), m= ½ ( b1 + b2)
(2) Engagement
  I will demonstrate identifying a trapezoid, identifying the component parts and calculating the area as well as the perimeter. I will demonstrate the Area Addition postulate can also be used by calculating both A and A and then adding their Areas.
| | Student Practice of New Material
(20 minutes)
| (5) Exploration/Application
Students will identify each base and the height in several trapezoid scenario’s, applying the appropriate formula to solve for the unknown component of the trapezoid in a table. Students will apply the Area formula to complete the table in their notebooks.
| | Summary
(5 minutes)
| (4) Assessment
An exit ticket to assess, hand out index cards. Students will express, in words, at least 2 ways to calculate the area, A, of trapezoid ADFG. Submit index card before departing class.
|
Part 3. Complete the below table in your notebook by applying the formula for the Area and perimeter of a trapezoid.
| b1
| 13 cm
| 13 m
| 9 ft
| 6 in
| | b2
| 7 cm
| 5 m
| 14 ft
| 12 in
| | h
| 5 cm
| 6 m
| 12 ft
| ?
| | A
| ?
| ?
| ?
| 48 in2
| | m
| ?
| ?
| ?
| ?
| | p
| ?
| 34 m
| 48 ft
| ?
|
Exit Ticket (describe how to find Area, A,of the trapezoid) :
G F
 H E
A B C D
Homework
Date: 2015-12-24; view: 690
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