You need the radius to work out the area of a circle, the formula is: circle area = πR 2. This means: π = Pi is a constant that equals 3.142. R = is the radius of the circle. R 2 (radius squared) means radius × radius.

Jan 06, 2020 · The formula to find the area of a circle is A = π r 2 {\displaystyle A=\pi r^{2}}, where the r {\displaystyle r} variable represents the radius. This variable is squared. Do not get confused and square the entire equation. For the sample circle with radius, r = 6 {\displaystyle r=6}, then r 2 = 36 {\displaystyle r^{2}=36}. The video provides two example problems for finding the radius of a circle given the arc length. Problem one finds the radius given radians, and the second problem uses degrees.

Circumference and area Two of the most basic formulas regarding circles are the formulas for area and circumference . The area of a circle is the number of square units that it takes to fill the inside of the circle. This worksheet may help you know about Circular Sector. A Circular Sector is portion of circle enclosed by two radii and an arc. The formula used to calculate the area of the circular Sector is, Formula Sector Area = (π r2 θ) / 360 Where, A is the Area of the circular sector. R is the radius of the circle. ANGLE is the central angle in radius. In this section we will discuss how to the area enclosed by a polar curve. The regions we look at in this section tend (although not always) to be shaped vaguely like a piece of pie or pizza and we are looking for the area of the region from the outer boundary (defined by the polar equation) and the origin/pole. May 31, 2008 · The key lies in the size of the angle. The area of its sector is 80cm sq. This area is a fraction of the area of the whole circle: 125/ 360. So, 80 x 360/125 sq.cm. will give you the area of the whole circle.

The formula for the area of a sector is (angle / 360) x height 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.