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Area

math Maturity 11-13 Vital Level 3

Area tells us how big a shape is.

SquareMeterQuadrat.JPG
SquareMeterQuadrat.JPG
It is how much paint we need to cover it. We can use small squares to measure it. This helps us know how much space we have. It is very useful! Can you find a big shape?

46 words

Area tells us how big a shape is.

SquareMeterQuadrat.JPG
SquareMeterQuadrat.JPG
It is how much paint we need to cover it. You can also think of it as the amount of material needed to make a shape.
RectangleLengthWidth.svg
RectangleLengthWidth.svg
We measure area by using small squares. A square metre is a common way to measure. It is a square with sides that are one metre long.
ParallelogramArea.svg
ParallelogramArea.svg
You can find the area of a rectangle by multiplying its sides. This helps us know how much space we have.

85 words

Area tells us how much space a flat shape covers.

RectangleLengthWidth.svg
RectangleLengthWidth.svg
You can think of area as the amount of paint needed to cover a surface. It is also how much material you would need to make a model of that shape.
SquareMeterQuadrat.JPG
SquareMeterQuadrat.JPG

We measure area using small squares. The standard unit is the square metre. This is a square with sides that are one metre long. You can also use smaller units like square centimetres. Or you can use larger units like square kilometres.

There are special ways to find the area of different shapes. For a rectangle, you multiply the length by the width.

ParallelogramArea.svg
ParallelogramArea.svg
You can also find the area of a triangle. A triangle is often half the size of a parallelogram.
TriangleArea.svg
TriangleArea.svg
For shapes with curves, like a circle, math becomes more complex. You can cut a circle into many small parts. These parts can be moved to look like a parallelogram.
CircleArea.svg
CircleArea.svg
This helps us find the area of the disk inside. Long ago, people like Archimedes used clever ways to study these shapes.

180 words

Area tells us how much space a flat shape covers on a surface.

RectangleLengthWidth.svg
RectangleLengthWidth.svg
You can imagine area as the amount of paint needed to cover a shape with one coat. It is also like the amount of material you would need to build a model of that shape. While length measures a single line, area measures a two-dimensional region. If you want to know the size of the boundary of a 3D object, that is called surface area.
Kugel-1-tab.svg
Kugel-1-tab.svg
Area is a very important part of math and geometry. It helps us understand how much space things take up in our world.

We measure area by comparing shapes to small squares.

SquareMeterQuadrat.JPG
SquareMeterQuadrat.JPG
In the International System of Units, the standard unit is the square metre. This is the area of a square with sides that are one metre long. You can also use square centimetres or square millimetres for smaller things. For very large spaces, people use square kilometres.
Area conversion - square mm in a square cm.png
Area conversion - square mm in a square cm.png
There are many different units depending on what you are measuring. For example, an acre is often used to measure land. Even tiny things in nuclear physics use a unit called a barn.

Finding the area of a shape often involves using special formulas.

RectangleLengthWidth.svg
RectangleLengthWidth.svg
For a rectangle, you find the area by multiplying the length by the width. A square is a special rectangle where all sides are the same. You can also find the area of a parallelogram by turning it into a rectangle.
ParallelogramArea.svg
ParallelogramArea.svg
Many other shapes are found by cutting them into pieces. A triangle can be seen as half of a parallelogram.
TriangleArea.svg
TriangleArea.svg
By dividing any polygon into triangles, you can find its total area. This method helps us solve many different math puzzles.

History shows that people have studied area for a very long time.

Archimedes sphere and cylinder.svg
Archimedes sphere and cylinder.svg
In the 5th century BCE, Hippocrates of Chios studied the area of a disk. Eudoxus of Cnidus also found that a disk's area relates to its radius. The famous mathematician Archimedes used clever methods to study circles. He showed that a circle's area is like a specific right triangle.
CircleArea.svg
CircleArea.svg
Later, Brahmagupta created a formula for certain four-sided shapes in the 7th century CE. In the 17th century, René Descartes helped create new ways to find areas. These discoveries helped lead to the invention of calculus.

Area is used in many different ways in modern science. It is a basic property used in a field called differential geometry. It also relates to things like determinants in linear algebra.

Integral as region under curve.svg
Integral as region under curve.svg
When shapes have curved edges, mathematicians use calculus to find the area. This is because curves are harder to measure with simple squares. Calculus allows us to find the area under a curve very accurately.
Areabetweentwographs.svg
Areabetweentwographs.svg
Whether you are measuring a small square or a huge field, area is everywhere. It helps us describe the size of the world around us.

498 words

Area is the measurement of the size of a region on a surface. It describes how much two-dimensional space a shape covers. You can think of area as the amount of paint needed to cover a surface with one coat. It can also be the amount of material required to make a model of a shape. While length measures a one-dimensional line, area is a two-dimensional concept. If you measure the boundary of a three-dimensional object, that is called surface area.

Kugel-1-tab.svg
Kugel-1-tab.svg

To measure area, mathematicians compare shapes to squares of a fixed size. In the International System of Units (SI), the standard unit is the square metre (m²). A square metre is the area of a square with sides exactly one metre long.

SquareMeterQuadrat.JPG
SquareMeterQuadrat.JPG
Every unit of length has a corresponding unit of area. For example, you can use square centimetres (cm²), square millimetres (mm²), or square kilometres (km²). In non-metric systems, you might use square feet (ft²) or square miles (mi²). When converting, the area factor is the square of the length factor. For instance, there are 10 millimetres in a centimetre, but there are 100 square millimetres in one square centimetre.
Area conversion - square mm in a square cm.png
Area conversion - square mm in a square cm.png

Calculating area often involves using specific formulas for different shapes. The most basic formula is for a rectangle, where area equals length multiplied by width.

RectangleLengthWidth.svg
RectangleLengthWidth.svg
A square is a special rectangle where all sides are equal, so its area is the side length squared. Other shapes can be understood through a process called dissection. This means cutting a shape into smaller pieces and rearranging them. For example, a parallelogram can be cut and moved to form a rectangle.
ParallelogramArea.svg
ParallelogramArea.svg
A triangle can be seen as half of a parallelogram, so its area is half the base times the height.
TriangleArea.svg
TriangleArea.svg
You can find the area of any polygon by dividing it into several triangles.

Curved shapes require more advanced mathematical tools. For a circle, the area is related to its radius. You can imagine a circle divided into many small sectors. If you rearrange these sectors, they form an approximate parallelogram.

CircleArea.svg
CircleArea.svg
For more complex shapes with curved boundaries, mathematicians use calculus. The development of integral calculus in the late 17th century was largely motivated by the need to find these areas. Calculus allows us to find the area under a curve or the area between two different graphs.
Integral as region under curve.svg
Integral as region under curve.svg
Areabetweentwographs.svg
Areabetweentwographs.svg

Humans have been studying area for thousands of years. In the 5th century BCE, Hippocrates of Chios showed that the area of a disk is proportional to the square of its diameter. Eudoxus of Cnidus also discovered that the area is proportional to the radius squared. The mathematician Archimedes used Euclidean geometry to show that a circle's area equals a specific right triangle. This triangle has a base equal to the circle's circumference and a height equal to the radius. Archimedes also used a doubling method with polygons to approximate the area of a circle.

Archimedes sphere and cylinder.svg
Archimedes sphere and cylinder.svg

As time passed, new formulas were discovered for more complex polygons. In the 7th century CE, Brahmagupta created a formula for cyclic quadrilaterals, which are four-sided shapes inside a circle. Later, in 1842, Carl Anton Bretschneider and Karl Georg Christian von Staudt independently found a formula for any quadrilateral. In the 17th century, René Descartes developed Cartesian coordinates. This allowed mathematician Carl Friedrich Gauss to create the surveyor's formula in the 19th century. This formula can find the area of any polygon if you know the locations of its vertices.

Area is a fundamental concept used across many scientific fields. In geometry and calculus, it is essential for understanding shapes and curves. In linear algebra, area is related to the definition of determinants. In differential geometry, area is a basic property of surfaces. In advanced mathematical analysis, the area of a plane subset is defined using the Lebesgue measure. In higher mathematics, area is often viewed as a special case of volume for two-dimensional regions. Even in nuclear physics, scientists use a tiny unit called a barn to describe the cross-sectional area of interaction at the atomic scale.

696 words
🖼️ Images & Media (33)
File:SquareMeterQuadrat.JPG
SquareMeterQuadrat.JPG
File:Area conversion - square mm in a square cm.png
Area conversion - square mm in a square cm.png
File:RectangleLengthWidth.svg
RectangleLengthWidth.svg
File:ParallelogramArea.svg
ParallelogramArea.svg
File:TriangleArea.svg
TriangleArea.svg
File:CircleArea.svg
CircleArea.svg
File:Archimedes sphere and cylinder.svg
Archimedes sphere and cylinder.svg
File:Triangle_GeometryArea.svg
Triangle_GeometryArea.svg
File:Integral as region under curve.svg
Integral as region under curve.svg
File:Areabetweentwographs.svg
Areabetweentwographs.svg
File:Simple square with sides marked.svg
Simple square with sides marked.svg
File:Rechteck-ab.svg
Rechteck-ab.svg

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