Finding the area of a
Parallelogram
SWBAT find the area of a parallelogram by using
square units and the area formula.
Do Now
1.
At the grocery store, 8 apples are bruised. If 20% of the apples
are bruised, how many apples are there?
2.
There are 450 students at a middle school. If 20% of them are
going on a field trip, how many students are going on a field
trip?
3.
Erin wants to buy a new pair of shoes for $66.50. If she saves
$9.50 each week, how many weeks will it take her to save
enough money to buy the shoes?
4.
If Michael earned $50.43 in 6.15 hours, how much did he earn
each hour?
Review of Rectangles
•
Go over worksheet
•
Go over exit ticket
Important Vocab
•
Parallelogram- a flat shape with opposite sides parallel
and equal in length.
•
Polygon-a plane shape with straight sides. (Ex: rectangle,
parallelogram, triangle)
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Base- the bottom of a shape
Area of a Parallelogram
Let's use the same process as we did for the rectangle. How
many 1 ft2 tiles fit across the bottom of the parallelogram?
Area of a Parallelogram
If we continue to build upon the first row, what happens?
How tall is the parallelogram?
How can you tell?
How does this help us find the area of the parallelogram?
How do you find the area of a parallelogram?
Area Formula
To find the area of a parallelogram, we multiply the base x
the height.
Area=bh
Area = 60 cm2
What if….
We ONLY use base and height—even if another measurement is given.
4 in
3 in
5 in
What measurements would we use to find the area of this parallelogram?
Partner Problems
1.
Nishelle’s backyard is in the shape of a parallelogram.
The parallelogram has an area of 224 square feet and a
base of 14 feet. What is the height of the parallelogram?
2.
The windows in an office building are shaped like
parallelograms. The base of each window is 1.8 meters
and the height is 1.8 meters. What is the area of each
window?
3.
Leeza is making labels in the shape of parallelograms.
Each label has an area of 18 square centimeters and a
base of 6 centimeters. What is the height?