The area of a circle is pi *r^2. The square root of 4 meters 2 equals 2 meters. Diameter of Circle. A line that "just touches" the circle as it passes by is called a Tangent. The diameter is twice the radius or d = 2r. The area of circles with 4 meters diameter and 2 meters diameter are 4xpi and 1xpi square meters respectively. Watch this tutorial to see how it's done! A chord is a line that joins any two points on a circle. Here's an example of how to find the diameter of a circle if the circle's area is given: If the area of a circle is 12.56 m 2, the radius = the square root of 12.56 meters 2 /3.14. Calculates the area and circumference of a circle given the radius or diameter. The center of a circle is the midpoint of its diameter. (See Isoperimetric inequality.) Watch this tutorial to see how it's done! 12.56 meters 2 /3.14=4 meters 2. Enter the area contained within a circle. What is the perimeter of a quadrant of a circle with radius 3cm? And a part of the circumference is called an Arc. Sometimes the word 'diameter' is used to refer to the line itself. If it passes through the center it is called a Diameter. I am installing a 1 yard-wide walk around circular swimming pool that is 21 ft in diameter. This is the diameter of a circle that corresponds to the specified area. ø = Circle diameter; A = Circle area; π = Pi = 3.14159… Area of Circle. Area and circumference of circles. In that sense you may see "draw a diameter of the circle". A line that "just touches" the circle as it passes by is called a Tangent. Once you know the area, multiply it by 2 to get the diameter. A line that cuts the circle at two points is called a Secant. The circle is the shape with the largest area for a given length of perimeter. Area of a circle = (1/2 x diameter)2 x pi Area of a 24 inch diameter circle: (12 inches)2 x 3.1416 = 144 square inches x 3.1416 = 452.4 square inches Asked in Math and Arithmetic, Algebra, Geometry This free circle calculator computes the values of typical circle parameters such as radius, diameter, circumference, and area, using various common units of measurement. You can find the circumference by using the formula. Use 3.14 for pi to calculate the area of a circle when its diameter is given. Diameter is defined as the line passing through the center of a circle having two extremes on the circumference of a circle. The area of a circle with 6 meters diameter is 9xpi square meters. Since r is half the diameter d, we have r =d/2. Write the equation of a circle with a center at (-3,-4) and a radius of 3? The diameter is a special type of chord, a line that joins any two points of a circle. Just plug that value into the formula for the area of a circle and solve. Learn the relationship between the radius, diameter, and circumference of a circle. A line segment that goes from one point to another on the circle's circumference is called a Chord. Diameter. If it passes through the center it is called a Diameter. CCSS Math: 7.G.B.4. The formula used to calculate the circle diameter is: ø = 2 x √(A / π) Symbols. To calculate the area, you just need to enter a positive numeric value in one of the 3 fields of the calculator. The diameter of a circle, by contrast, is the longest distance from one edge of the circle to the opposite edge. Circle area calculator and circumference calculator provide you with a simple way of determining the square footage area for various shapes. If you have the diameter of a circle, you can use it to find the area of that circle. Just plug that value into the formula for the area of a circle and solve. You can also see at the bottom of the calculator, the step-by-step solution. And a part of the circumference is called an Arc. The circle is a highly symmetric shape: every line through the centre forms a line of reflection symmetry and it has rotational symmetry around the centre for every angle. A line segment that goes from one point to another on the circle's circumference is called a Chord. If the diameter (d) is equal to 10, you write this value as d = 10. Its mathematically accurate and useful for Construction projects, wood workers, home owners, students, and real estate. In the more recent sense, it is the length of the line, and so is referred to as "the diameter of the circle is 3.4 centimeters" The diameter is also a chord.