How do I calculate the area of ​​a quadrilateral?

What you need:

• Basic arithmetic
• Knowledge "square"

What is the area?

• The concept of area or simply area only applies to geometric figures that are two-dimensional, such as Quadrilaterals.
• This is the content limited by the figure. The area is thus a measure of everything that is inside the figure.
• The surface area can be illustrated by "painting" or "coloring" the area within the figure.
• Areas are (mostly) given in the units m² (square meters) or cm² (square centimeters), depending on which unit of length the delimiting sides have.

Area of ​​a rectangle - this is how you calculate it

• However, one quadrangle is not always the same, because there are very different types in this geometric group. And so you also have to calculate the area differently.


Find the length of the sides of a rectangle - here's how

In math class, you will learn about various geometric shapes that you ...

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• The simplest square is undoubtedly the square (which, curiously, many people simply refer to as "square"!). In this particularly simple square, all sides are of the same length and are perpendicular to one another. The area is simply calculated as A = a², where A is the abbreviation for the area (from lat. "area") and "a" represents the side length of the square.
• In the case of a rectangle, the two opposite sides are each of the same length and are perpendicular to one another. Usually the two sides are referred to as length and width. The formula A = a x b (length times width) applies to the area.
• Parallelograms are more complicated quadrilaterals. With them, the two opposite sides are of the same length and parallel (hence the name), the angle however, they are not (necessarily) 90 ° between the sides. You can calculate the area of ​​this square by knowing the height of the figure: This line is perpendicular to one of the two (known) sides and goes through the opposite corner. The formula then results in A = a x h (where a is the length of the side and h is the height of the parallelogram).
• With a trapezoid, only two opposite sides (called a and c) are parallel (and not necessarily the same length). Here, too, the area depends on the height of the figure: A = (a + c) x h / 2.
• A special square is the dragon square (the shape is known from the corresponding aircraft), in which the The area is given by the two diagonals: A = e x f (where e and f denote the length of the two Diagonals).
• But what if the square for which you are supposed to calculate the area does not belong to any of the special square groups mentioned, but lies in front of you (completely irregularly)? This problem can also be solved by dividing the square in two Triangles and its area calculated (base side x height divided by 2). However, it can happen to you that you first have to calculate the heights of the two triangles with the trigonometric functions sine or tangent.