Perimeter of a sector of a circle???
Find the approximate perimeter of a sector of a circle with a radius of 6m and the angle measures of 84 degrees or (7pi/15). Give the exact answer, and an answer rounded to two decimal places.
I am really lost here!! please help =)
Top 3 Answers
Favorite Answer
Well, we need to find the circumference of the circle first. The formula is 2* pi* r. That’s 2 times 3.1415 times 6 meters or 37.698 meters. The perimeter of the sector of the circle is equal to 2 times r (for both of the legs of the sector) + (84/360 times the circumference of the circle. Well the two legs are 6 meters each (12 meters) and the length of the arc is 84/360 (or .233) times 37.698 meters. Well, .233 times 37.698 is 8.796.
6 plus 6 plus 8.796 is 20.796 or 20.80 meters rounded to two places.
I’ve given you more places than you needed in the calculations.
Please keep in mind that the perimeter of the sector includes the arc AND the sides. Imagine a slice of pizza as a sector. The perimeter includes both the crust and the two cut edges.
0
5 years ago
Let r = radius of the circle f = fraction of the circle that make up the sector. Perimeter = 2 pi r f + 2r = 7 Area = pi r^2 f = 3 pi f = 3/r ^ 2 by substitution 6/r + 2r = 7 2 r^2 – 7r + 6 = 0 (2r -3)(r-4)=0 r = 3/2 or 4
0
C=2*pi*r
L=2*a/360*pi*r
= (a*pi*r)/180
where L is the length of the sector of the circle,
r is the radius of the circle
a is the angle that the sector makes if you connect the endpoints of the sector to the centerpoint of the circle
L = (84*pi*6m)/180
= 4.40m
0
