Tip 1: How to find the length if the area and width are known

The science

Tip 1: How to find the length if the area and width are known

When solving geometric problems, usually one parameters are calculated, if others are known. For example, if given area and width rectangle, you can find it long. Similar problems often have to be solved in practice - when measuring or planning the living space, land or purchase of building materials.

You will need

calculator

Instructions

To find long side of the rectangle, if known width and area, divide the numerical value of the area by the numerical value of the width. That is, use the formula: Д = П / Ш, where: Д - length of the side of the rectangle, Ш - width rectangle, P is its area.For example, if area The rectangle is 20 cm², and its width - 5 cm, then the length of his side will be: 20/5 = 4 cm.

Before starting calculations, set the width and area rectangle into one measurement system. I.e, area should be expressed in the corresponding width of the square units of measurement. In this case, the length is obtained in the same units as width. So, if width is set in meters, then area must be converted into square meters. This translation is especially relevant when measuring land plots, where area is usually specified in hectares, araks and "weave".

For example, suppose area country plot is equal to six weave, and its width - 30 meters. Required to find long Since 100 square meters is called "weaving", area "Standard" six hundred square meters can be written as 600 m². From here long The land plot can be found by dividing 600 by 30. It turns out - 20 meters.

Sometimes given area and width figure, which has not a rectangular, but an arbitrary shape. In this case, it is also required to find it long. As a rule, in this case we meanthe overall dimensions of the shape, that is, the parameters of the rectangle into which this shape can be enclosed. If the accuracy of the calculations is not high, then use the formula above (A = N / N). However, the length value will be too low. To get a more accurate value for the length of the shape, estimate how fully the shape fills its dimensional rectangle and divide the resulting long on the filling factor.

So, for example, if the lake has area 100 square kilometers, its width equal to 5 kilometers and it takes about half the overall rectangle, then its length will be: 100/5 / 0,5 = 40 kilometers.

Tip 2: How to find the area of a rectangle: the solution

Each geometric figure hascertain characteristics, which, in turn, are related to each other. Therefore, in order to find the area of the rectangle, you need to know what the length of its sides is.

Rectangle - one of the most commongeometric figures. It is a quadrilateral, all angles of which are equal to each other and make up 90 degrees. This characteristic, in turn, entails certain consequences with respect to the other parameters of the figure in question. First, its sides, facing each other, will be parallel. Secondly, these sides will be equal in pairs to each other in length. These characteristics of the rectangle are very important for calculating its other parameters, such as area.

How to calculate the area of a rectangle

In order to calculate the area of the rectangle,It is necessary to have information about the length of its sides. It should be remembered that the sides of the rectangle are not equal in this indicator: a rectangle, all sides of which are equal in length, represents another geometric figure, which is called a square. Therefore, to designate the different sides of the rectangle, special notations are adopted: thus, a side with a large extent is usually called the length of the figure, and the side with a smaller length is its width. In this case, each rectangle, due to its properties described above, has two lengths and two widths. Actually, the algorithm for calculating the area of this figure is quite simple: it is only necessary to multiply its one length by one its width. The resulting product will be the area of the rectangle.

Example calculation

Suppose there is a rectangle, one sidewhich is 5 centimeters, and the other - 8 centimeters. Thus, according to the above definition, the length of this figure, measured as the length of the larger side, will be 8 centimeters, and the width - 5 centimeters. To find the area of a figure, it is necessary to multiply its width by the length: thus, the area of the rectangle under consideration is 40 square centimeters. Note that in order to perform calculations, both used parameters should be measured in the same units, for example centimeters, as in this case. If they are given in different units, you need to bring them to a common measurement. So if the length of the rectangle is equal to, for example, 8 centimeters and the width to 0.06 meters, according to the conditions of the problem, the width should be converted into a measurement in centimeters. Its size in this case is 6 centimeters, and the area of the figure is 48 square centimeters.