Square centimeters are a metric unit of measure of the area of various flat geometrical figures. It has universal application, since a school bench and finishing calculations at the level of architecture and mechanics. To find square centimeters not really difficult
Instruction
1. The square centimeter figuratively represents a square at which length of the party is 1 cm. Triangles, rectangles, rhombuses and other geometrical figures can include not one such square. Thus, the square centimeter, in essence, is one of the most often applied units of measure of the area of figures in the school program.
2. The areas of various flat geometrical figures it is calculated on a miscellaneous: S = a² is the area of a square where a - length of any of its parties; S = a*b is the area of a rectangle where an and b - the parties of this figure; S = (a*b*sinα)/2 - the area of a triangle, an and b - the party of this triangle, α - a corner between these parties. Actually, there is a lot of formulas for calculation of the area of a triangle; S = ((a + b) *h)/2 - the area of a trapeze, an and b - the basis of a trapeze, h - its height. Formulas on calculation of the area of a trapeze also exists a little; S = a*h is the area of a parallelogram, and - the party of a parallelogram, h - height which is carried out to this party. The formulas given above - not everyone by means of which it is possible to calculate the areas of various geometrical figures.
3. In order that it was more clear how to find square centimeters, it is possible to give several examples: Example 1: The square at which length of the party is 14 cm is given, it is necessary to calculate its area. It is possible to solve a problem by means of one of data above formulas: S = 14² = 196 cm²Ответ: the area of a square is 196 cm²Пример 2: There is a rectangle which length of 20 cm, and width of 15 cm, besides is required to find its area. It is possible to solve an objective by means of the second formula: S = 20*15 = 300 cm²Ответ: the area of a rectangle is 300 cm²
4. If in a task units of measure of the parties and other parts of a figure are not centimeters, and, for example, meters or decimeters, then to express the area of this figure in centimeters besides very easily. Example 3: Let the trapeze which bases are equal 14 m and 16 m, height of its 11 m be given. It is required to calculate the area of a figure. For this purpose it is necessary to use the fourth formula: S = ((14+16)*11)/2 = 165 m² = 16500 cm² (1 m = 100 cm) Answer: the area of a trapeze is 16500 cm²