The circumference can be found … The area of an oval is the longest diameter x the shortest x 0.7854. Michael. Circumference of circle with radius 3 is 18.85 Circumference of circle with radius r is 2pir, where pi=3.1416. What is the area of the circle? 1 decade ago. A = 81π . In the process, Diameter= 18, Radius(r)= (18)/2 :. r = 9. 2 See answers michellehu8888 michellehu8888 The area of the circle is 81 pi inches. alpha. The circle is divided into 16 equal sectors, and the sectors are arranged as shown in the fig. Area of a sector formula. - 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. 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) (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. 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. Lv 7. Visit https://www.MathHelp.com.This lesson covers the area of a circle. Henry knows that the circumference of a circle is 18 pi inches. The area can be found by multiplying PI (3.14159) times the radius times the radius again. Step-by-step explanation: New questions in Mathematics. 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. The area, A of the circle with radius r is given by \(A\) = \(π~r^2\) Definition 3: The portion of the circle enclosed by two radii and the corresponding arc is known as the sector of a circle. New questions in Mathematics. Area = 81π cm². P.S. Plug that into the formula: A = π9² . Well, the semicircle is half of the circle, so if I want the area of the semicircle, this is gonna be half this. Answer Save. 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. Area of a circle can be visualized & proved using two methods, namely. Formulas, explanations, and graphs for each calculation. 1 See answer nafissmith23 is waiting for your help. Find the area of a circle circumscribed about an equilateral triangle whose side is 18 inches long. The radius is half the diameter (9 inches). 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. Find the diameter of the circle 2 See answers tonb tonb The circumference is π times the diameter (2r). C x 34 = Show Your work WHY AM I DOING SCHOOL AT 2AM -.- DAAAAAANG, YALL SMART :O CAN U HELP WITH THIS ONE THOUGH? 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) 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. But instead of a 16 inch diameter, it's now an 18 inch diameter circle. … 0 1. Square feet can also be expressed as ft 2 or sq. inches. (diameter x pi = circumference). Radius= 9 Now, Circumference (Perimeter) = ? How to Calculate Area. First we need to know that the area of a circle is a function of the radius. Lv 5. Enter the area contained within a circle. As such, circumference of circle with radius 3 is 2xx3.1416xx3 or 6xx3.1416=18.8496~=18.85 , The formula to find the area of the segment is given below. 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 Add your answer and earn points. r=.5d=18/2=9. Answer: 81π sq. It’s the size of a 2-dimensional surface and is measured in square units, for example, square feet. Determine the area of the shaded sector. What is the area of a circle, if the diameter is 18? It would hence be right to say that a semi-circle or a quarter-circle is a sector of the given circle. A circle has an area of M cm^2 and a circumference of N cm. Circumference of a circle formula. A circular pizza that is 18 inches in diameter is cut into 8 equal slices. d = 18.84/ PI. musiclover10045 musiclover10045 circumference = PI x D 18.84 = PI x D . Also, assuming the same radius and diameter for a sphere, the surface area and volume of that sphere are returned. Thus, the area of a circle with a circumference of 18π centimeters is 81π squared centimeters. The area is measured in units such as square centimeters $(cm^2)$, square meters $(m^2)$, square kilometers $(km^2)$ etc. Note the number of square units it takes to fill it. 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) A circle is 0.7854 times as heavy as a square of the same size. (d)Diameter of a circle is always equal to two times of (r)radius. If the diameter is 18 inches, what is the radius? Area of Circle. Relevance. Aaron. Step-by-step explanation: The area of a circle is pi×radius^2. Therefore radius r=9 units. To find area from the circle's diameter: a = \pi (d/2)^2. Lv 5. 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) Area of a triangle calculation using all different rules, side and height, SSS, ASA, SAS, SSA, etc. You can enter the diameter and then compute radius and circumference in mils, inches, feet, yards, miles, millimeters, centimeters, meters and kilometers. The circumference of a circle is 18.84 inches. Circumference The distance around the outward boundary of a circle, expressed as a linear unit of measurement (millimeters, inches, etc.). The perimeter is measured in units such as centimeters,meters, kilometers, inches, feet, yards, and miles. If M/N=20, what is the radius of the... See all questions in Connection to Areas Using the Diameter Calculator. What is 9²?--> 9 * 9 = 81 . Jamayaa Jamayaa Answer: 81. 6 years ago. Area = (π)(9 cm)². Diameter of Circle. [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. This is the diameter of a circle that corresponds to the specified area. So instead of four pi, it is going to be two pi square units. 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. 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. 1 decade ago. NLattig8833 NLattig8833 Answer: 31.8 in^2. 1 See answer mcenaneykaitlyn3894 is waiting for your help. Let's do another example. 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 . The formula for the area of a circle is: A = πr² . Area is the space inside the perimeter/boundary of space, and its symbol is (A). Area=Pi*r^2 =3.14*81 =254.34 sq units. Basically, a sector is the portion of a circle. Add your answer and earn points. 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. Definition: The number of square units it takes to fill a segment of a circle Try this Drag one of the orange dots that define the endpoints of the segment. d = 6 inches. (Answer) 0 0. That's the area of the semicircle. 10 Answers. 10950 Lin-Valle Dr. Saint Louis, MO 63123 - (800) 462-7447 - … Rounded, the answer is 6.00 inches. Area of a Circle Segment Given the Central Angle. The diameter of the circle will be 30 inches. A=(3.14159)(9^2)=(3.14159)(81)=254.5. Favorite Answer [1] Diameter is 18 units. So if you divide the given 18.84 by π, you get the diameter. 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. Solution for A circle has an 18-inch radius and a shaded sector with a central angle of 50°. Need a custom math course? 18*pi or 18*3.141592=56.55. 3. What is the area of a single slice? The circumference of a 4-inch diameter circle is: about 12.57 inches. 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