Lesson on Area of Parallelograms
![[IMAGE]](./Lesson%20on%20Area%20of%20Parallelograms_files/image001.gif)
The area of a polygon is the number of square
units inside the polygon. Area is 2-dimensional like a carpet or an area rug.
A
parallelogram is a 4-sided shape formed by two pairs of parallel lines. Opposite sides
are equal in length and opposite angles are equal in measure. To find the area
of a parallelogram, multiply the base by the height. The formula is:
where 
is the base, 
is the height, and · means
multiply.
The base and height of a parallelogram must be perpendicular. However, the lateral sides of a parallelogram are not perpendicular to the base. Thus, a dotted line is drawn to represent the height. Let's look at some examples involving the area of a parallelogram.
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Example
1: |
Find
the area of a parallelogram with a base of 12 centimeters and a height of 5
centimeters. |
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Solution:
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![[IMAGE]](./Lesson%20on%20Area%20of%20Parallelograms_files/image006.gif)
= (12 cm) · (5 cm)
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Example
2: |
Find
the area of a parallelogram with a base of 7 inches and a height of 10 inches.
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Solution:
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![[IMAGE]](./Lesson%20on%20Area%20of%20Parallelograms_files/image010.gif)
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Example
3: |
The
area of a parallelogram is 24 square centimeters and the base is 4
centimeters. Find the height. |
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Solution:
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24 cm2
= (4 cm) · |
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24 cm2
÷ (4 cm) = |
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![[IMAGE]](./Lesson%20on%20Area%20of%20Parallelograms_files/image012.gif)
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Summary: |
Given
the base and height of a parallelogram, we can find the area. Given the area
of a parallelogram and either the base or the height, we can find the missing
dimension. The formula for area of a parallelogram is: |
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