Instruction

1

Diameter is the segment connecting two arbitrary points on the

**circle**and passing through its center. Therefore, if**the diameter**you need to find by knowing the radius of the given**circle**, multiply the numerical value of the radius by two, and measure the value found in the same units as the radius. Example: the Radius**of a circle**4 centimeters. To find**the diameter**of this**circle**. Solution: the Diameter is 4 cm*2=8 cm Answer: 8 inches.2

If the diameter of the need to find through the length

**of the circle**, then we must act using the first step. There is a formula to calculate the length**of a circle**: l=2PR, where l is the length**of the circumference**, 2 is a constant, n is the number equal to 3.14; R is the radius**of the circle**. Knowing that**the diameter**is double the radius, the above formula can be written as: l=пD, where D is**the diameter**.3

To Express this formula

**diameter****of circle**: D=l/n, And substitute into it the known values, calculate a linear equation with one unknown. Example: to Find**the diameter****of a circle**if its length is 3 meters. Solution:**the diameter**is equal to 3/3 = 1 m. Answer:**the diameter**equal to one meter.Useful advice

In the mathematical tasks are often permitted to use the PI as just 3, and 3.14.