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Hey Brob its Danielle from first hour again. Im gonna come see you at lunch cause i think your email hates my email cause it never sends so i"m stuck using Sarahs again.

*Formula 1: k=(1/2)r^2(theta)

-k is the area of a sector

-r is the radius

-s is the arc length

-theata is the central angle

*Formula 2: k=(1/2)rs

-r is the radus

-s is the arc length

-k is the area of sector

*Formula 3: s=r(theta)

-r is the distance between two objects

- theta is the apparent size

-s diameter fo an object

Example 1: A sector of a circle has a radius 6 cm and central angle 0.5 radians. Find its arc length and area.

-r= 6cm

-theta= 0.5

-s= ?

k= ?

-I would use forumula 1 to find k. k=(1/2)r^2(theta)

k=(1/2)(6)^2(0.5) *You multiply them all

k=9 cm

-Now i would use formula 2 to find s. k=(1/2)rs

9=(1/2)(6)s *First you multiply 1/2 times 6 which will give you 9=3s and then you divide 3 by 9.

s= 3 cm

Example 2: A sector of a circle has arc length 2 cm abd central angle 0.4 radians. Find its radius and area.

-s= 2cm

-theta= 0.4

-k= ?

-r= ?

-I would use formula 3 first to dins r. s=r(theta) *To find r it would be r= s/theta

r= 2/0.4 r= 5 cm

- Now i would use formula 1 to find k. k=(1/2)r^2(theta)

k=(1/2)(5)^2(0.4) k= 5 cm

--Danielle