To convert diameter to area , you will need to divide the diameter by two so as to get the radius. The result you get, square it and them multiply it by 3.14 to find the area.
In order to do this, you must have the radius in feet.-- Square the radius (multiply it by itself)-- Multiply the answer by 'pi'. (3.142 is close enough)-- The answer is the area of the circle, in square feet.
assuming the island is circular.... use the formula Area=(pi)x(radius squared) to find the radius, then use the formula C=2(pi)(radius) to determine the circumference.
2 x pi x radius
Diameter is half of the radius. Times it by 2.
Use the formula for the area of a circle: area = pi x radius2. Then convert square miles to acres.
The area of a semicircle is half of the area of a circle. The area of a circle is pi x radius x radius. So the area of a semicircle is 1/2 x pi x radius x radius or (pi x radius x radius) / 2.
The area increases as the square of the radius (or diameter). So if you double the radius you * 4 (quadruple) the area. Treble the radius, you *9 the area.
Area = π × radius² → radius² = area/π → radius = √(area/π) Circumference = 2 × π × radius = 2 × π × √(area/π) = √(2² × π² × area/π) = √(4 × π × area)
When you try to figure out an area of a circle, you square the radius, then multiply it by pi to get the area of a circle. A radius square is radius x radius, or radius squared.
Circumference = 2*pi*radius Radius = Circumference/(2*pi)
Multiply the radius by itself, then multiply the result by Pi.