How to find the area of irregular shapes

In the school course of geometry students mostly consider square and regular polygons. Meanwhile, to solve many practical problems often have to deal with irregular geometric figures. With this problem people faced when determining the size of suburban area or local area, and to calculate the amount of fabric for sewing, and in many cases. To calculate the area of irregular shapes in several ways.

You will need

• - irregular geometric figure;
• measuring tools;
• - transparent plastic;
• - the range;
• - gon;
• - ballpoint pen.

Instruction

1. Consider the geometric shape and determine what parameters of it are known to you. It can be the lengths of the sides or corners. Depending on the specified parameters and select the method of determining the area. For example, divide it into multiple shapes, the formulas for calculating the area of which you know. One of the most common methods is to swipe diagonally from one corner to all other vertices. In this case, you need to know the formula for calculating the area of an arbitrary triangle. But nobody forbids to divide a given shape and other polygons. For example, in the calculation of floor space in a room with a niche to separate the irregular figure into two rectangles or squares.
2. To determine the area is not too big of a part, use the palette. It is possible to do yourself. Cut a rectangular piece of any transparent plastic. Divide it into squares, the area of which you are aware — for example, 1x1 or 0,5x0,5 cm Ruler and a square to be exact. Apply the palette to the item. Count full squares, then incomplete. The number of incomplete squares, divide by 2 and add the result to the number of whole. The smaller the graduations on the palette, the more accurate the result. Similarly we can calculate square footage. The role of samples will carry out a grid of squares with sides 1x1 m drawn on the ground or marked with pegs between them with outstretched cords. We can restrict and marking of territory at the strip. .
3. With large squares alternatively. Take the most accurate site plan or local area. Define the scale. Use one of the following ways. Then the number of square inches put in the necessary scale.