Question

Діаметр кола 20 см знайдіть радіус . площу круга і довжину кола​

Answer 1

Ответ:

радіус 10см

Пошаговое объяснение:

r=d÷2 r=20÷2

r=10

Answer 2

Ответ:

радіус:10см

площа≈ 314 см^2

довжина≈62,8см

Answer 3

Calculating the Radius of a Circle

To find the radius of a circle when the diameter is given, you can simply divide the diameter by 2.

Given that the diameter of the circle is 20 cm, we can calculate the radius as follows:

Radius = Diameter / 2

Radius = 20 cm / 2

Radius = 10 cm

Therefore, the radius of the circle is 10 cm.

Calculating the Area of a Circle

The formula to calculate the area of a circle is:

Area = π * r^2

where π (pi) is a mathematical constant approximately equal to 3.14159, and r is the radius of the circle.

Using the radius we calculated earlier (r = 10 cm), we can calculate the area of the circle as follows:

Area = π * (10 cm)^2

Area ≈ 3.14159 * 100 cm^2

Area ≈ 314.159 cm^2

Therefore, the area of the circle is approximately 314.159 cm^2.

Calculating the Circumference of a Circle

The formula to calculate the circumference of a circle is:

Circumference = 2 * π * r

Using the radius we calculated earlier (r = 10 cm), we can calculate the circumference of the circle as follows:

Circumference = 2 * 3.14159 * 10 cm

Circumference ≈ 62.8318 cm

Therefore, the circumference of the circle is approximately 62.8318 cm.

Please note that the values for pi and the calculated area and circumference are approximate due to the rounded values used for pi.