Area of sector JFK=70degree JD=7cm

## How do you do area of sector

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# 2 Answers

A sector is some portion of a circle.

Formula for area of a circle is A =(pi)r

^{2}For the area of some sector with x degrees lets use a proportional relationship

Area

_{sector}x degrees____________ = _____________

Area

_{circle }360 degrees(AREAsector) =
70

(pi) r

^{2}360Solve by cross multiplication.

Hi, Abby!

A sector is simply a piece of a circle. The easiest way to find the area of a sector is to find the area as if it were a complete circle (Area of a circle is pi*r

^{2}.) and then multiply it by a ratio to represent the size of the sector compared to a whole circle (degree/360).In your question, where JFK = 70 degrees and JD = 7cm, I am going to assume that JD is the diameter of what would be the whole circle (If it is the radius, then you can just use 7 for r).

radius = r = 1/2 * diameter = 1/2 * 7 = 3.5

Area = pi * r

^{2}* (degrees/360)Area = 3.14 * (3.5)

^{2}* (70/360)Area = 3.14 * 12.25 * 70/360

Area = 7.48 cm

^{2}Hope this helps!

Patty