A circle of radius = 12 or diameter = 24 or circumference = 75.4 inches has an area of: 2.9187 × 10-7 square kilometers (km²); 0.29187 square meters (m²) 2918.7 square centimeters (cm²) 1 decade ago. (d)Diameter of a circle is always equal to two times of (r)radius. d = 6 inches. How to Calculate Area. Note the number of square units it takes to fill it. 0 1. With this semicircle area calculator, you can quickly find the area of half of a circle.What is more, the tool also doubles as a semicircle perimeter calculator, so inputting radius or diameter will help you find the basic features of the shape in the blink of an eye.In the article below, we provide the semicircle definition and explain how to find the perimeter and area of a semicircle. What is the area of a single slice? Area is the space inside the perimeter/boundary of space, and its symbol is (A). Find the diameter of the circle 2 See answers tonb tonb The circumference is π times the diameter (2r). Lv 5. What is 9²?--> 9 * 9 = 81 . The area can be found by multiplying PI (3.14159) times the radius times the radius again. P.S. inches. That's the area of the semicircle. Plug that into the formula: A = π9² . 1 See answer nafissmith23 is waiting for your help. Area = 81π cm². Square feet can also be expressed as ft 2 or sq. Radius= 9 Now, Circumference (Perimeter) = ? Enter the area contained within a circle. According to the formula, Perimeter= 2 xx (22)/7 xx r Taking the equation, Perimeter= 2 xx (22)/7 xx r rArr2 xx (22)/7 xx 9 rArr (396)/7 rArr 56.57142857 rArr 56.57 Let's hope this helps you:) Geometry . Determining the circle’s area using rectangles; Determining the circle’s area using triangles; Let us understand both the methods one-by-one-Using Areas of Rectangles. Area of Circle. A circle of radius = 6 or diameter = 12 or circumference = 37.7 inches has an area of: 7.29676 × 10-8 square kilometers (km²); 0.0729676 square meters (m²) 729.676 square centimeters (cm²) Henry knows that the circumference of a circle is 18 pi inches. But instead of a 16 inch diameter, it's now an 18 inch diameter circle. Find the area of a circle circumscribed about an equilateral triangle whose side is 18 inches long. Favorite Answer [1] Diameter is 18 units. In the process, Diameter= 18, Radius(r)= (18)/2 :. Also, assuming the same radius and diameter for a sphere, the surface area and volume of that sphere are returned. musiclover10045 musiclover10045 circumference = PI x D 18.84 = PI x D . Enter any of the four circle values, area, radius, diameter or circumference, click on Calculate and the other three values are returned in full (up to 18 decimal places) and maximum 3 decimal place rounded values. The formula for the area of a sector is (angle / 360) x π x radius 2.The figure below illustrates the measurement: As you can easily see, it is quite similar to that of a circle, but modified to account for the fact that a sector is just a part of a circle. The circumference can be found … … Step-by-step explanation: New questions in Mathematics. Area=Pi*r^2 =3.14*81 =254.34 sq units. [6] 2020/10/08 18:09 Male / Under 20 years old / Elementary school/ Junior high-school student / Useful / Purpose of use Helped me with finding areas of a circle. C x 34 = Show Your work WHY AM I DOING SCHOOL AT 2AM -.- DAAAAAANG, YALL SMART :O CAN U HELP WITH THIS ONE THOUGH? 18*pi or 18*3.141592=56.55. Area = (π)(9 cm)². The area of an oval is the longest diameter x the shortest x 0.7854. A = 81π . You can enter the diameter and then compute radius and circumference in mils, inches, feet, yards, miles, millimeters, centimeters, meters and kilometers. 800 Square Inches to Circular Inches = 1018.5916: 20 Square Inches to Circular Inches = 25.4648: 900 Square Inches to Circular Inches = 1145.9156: 30 Square Inches to Circular Inches = 38.1972: 1,000 Square Inches to Circular Inches = 1273.2395: 40 Square Inches to Circular Inches = 50.9296: 10,000 Square Inches to Circular Inches = 12732.3954 In geometry, the area enclosed by a circle of radius r is πr 2.Here the Greek letter π represents the constant ratio of the circumference of any circle to its diameter, approximately equal to 3.14159.. One method of deriving this formula, which originated with Archimedes, involves viewing the circle as the limit of a sequence of regular polygons. A circle of radius = 5 or diameter = 10 or circumference = 31.42 inches has an area of: 5.06709 × 10-8 square kilometers (km²); 0.0506709 square meters (m²) 506.709 square centimeters (cm²) Times the radius of the circle squared, and you say, well they gave us the diameter, what is the radius? It would hence be right to say that a semi-circle or a quarter-circle is a sector of the given circle. The formula to find the area of the segment is given below. Circumference The distance around the outward boundary of a circle, expressed as a linear unit of measurement (millimeters, inches, etc.). Rounded, the answer is 6.00 inches. Add your answer and earn points. What is the area of a circle, if the diameter is 18? The circumference of a circle is 18.84 inches. A circle of radius = 2.998 or diameter = 5.997 or circumference = 18.84 centimeters has an area of: 2.825 × 10-9 square kilometers (km²); 0.002825 square meters (m²) 28.25 square centimeters (cm²) The circle is divided into 16 equal sectors, and the sectors are arranged as shown in the fig. If M/N=20, what is the radius of the... See all questions in Connection to Areas First we need to know that the area of a circle is a function of the radius. Visit https://www.MathHelp.com.This lesson covers the area of a circle. Using the Diameter Calculator. Need a custom math course? The diameter of the circle will be 30 inches. New questions in Mathematics. d = 18.84/ PI. The area is measured in units such as square centimeters $(cm^2)$, square meters $(m^2)$, square kilometers $(km^2)$ etc. (diameter x pi = circumference). The radius is half the diameter (9 inches). Let's do another example. A=(3.14159)(9^2)=(3.14159)(81)=254.5. Circumference of a circle formula. Add your answer and earn points. Step-by-step explanation: The area of a circle is pi×radius^2. Basically, a sector is the portion of a circle. - 8929571 nafissmith23 nafissmith23 02/27/2018 Mathematics College Find the area of a circle circumscribed about an equilateral triangle whose side is 18 inches long. If the diameter is 18 inches, what is the radius? So if you divide the given 18.84 by π, you get the diameter. Area of a triangle calculation using all different rules, side and height, SSS, ASA, SAS, SSA, etc. Michael. 6 years ago. So instead of four pi, it is going to be two pi square units. r = 9. It’s the size of a 2-dimensional surface and is measured in square units, for example, square feet. Area of a sector formula. Area of a Circle Segment Given the Central Angle. The formula for the area of a circle is: A = πr² . NLattig8833 NLattig8833 Answer: 31.8 in^2. Formulas, explanations, and graphs for each calculation. A circle is 0.7854 times as heavy as a square of the same size. Jamayaa Jamayaa Answer: 81. Relevance. alpha. Circumference of circle with radius 3 is 18.85 Circumference of circle with radius r is 2pir, where pi=3.1416. And so when we think about area, we know that the area of a circle, the area of a circle is equal to pi times the radius of the circle squared. Well, the semicircle is half of the circle, so if I want the area of the semicircle, this is gonna be half this. Since the formula for the area of a circle squares the radius, the area of the larger circle is always 4 (or 2 2) times the smaller circle.Think about it: You are doubling a number (which means ×2) and then squaring this (ie squaring 2) -- which leads to a new area that is four times the smaller one. What is the area of the circle? (18(π) cm) = 2(π)r (18(π) cm)/(2(π)) = r. 9 cm = r. Now since we found that the value of radius r is 9 cm, we can solve for the area of the circle using the formula mentioned early: Area = (π)r². (Answer) 0 0. 10950 Lin-Valle Dr. Saint Louis, MO 63123 - (800) 462-7447 - … Answer: 81π sq. 1 decade ago. Diameter of Circle. Aaron. An easy to use, free area calculator you can use to calculate the area of shapes like square, rectangle, triangle, circle, parallelogram, trapezoid, ellipse, octagon, and sector of a circle. Lv 5. As such, circumference of circle with radius 3 is 2xx3.1416xx3 or 6xx3.1416=18.8496~=18.85 , 3. Thus, the area of a circle with a circumference of 18π centimeters is 81π squared centimeters. This is the diameter of a circle that corresponds to the specified area. The perimeter is measured in units such as centimeters,meters, kilometers, inches, feet, yards, and miles. Answer Save. The circumference of a circle is calculated using the formula: 2 x π x radius, where π is a mathematical constant, equal to about 3.14159.It was originally defined as the ratio of a circle's circumference to its diameter (see second formula below on why) and appears in many formulas in mathematics, physics, and everyday life. Lv 7. Given: radius of a circle = 15 inches Required to find - diameter Solution: d = 2r d = 2x15 d=30 Therefore the diameter of the given circle will be 30 inches. Area of a circle can be visualized & proved using two methods, namely. 1 See answer mcenaneykaitlyn3894 is waiting for your help. 10 Answers. A circular pizza that is 18 inches in diameter is cut into 8 equal slices. To find area from the circle's diameter: a = \pi (d/2)^2. r=.5d=18/2=9. Determine the area of the shaded sector. A circle has an area of M cm^2 and a circumference of N cm. 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