Dom's blog # 1

chapter 7-2
all you have to do is remember the formulas and the hints to pass this section
formulas
s=r(theta)
k-one half(r)squaredtheta
k=onehalf (r)(s)
s=arc length
r=radius
theta=central angle
k=area
theta=apparent size
s=diameter
r=distance between objects
Ex: A sector of a circle has an arc length of 8 cm and the area of 75 cm. Find its radius and the measure of its central angle.
s=8cm
k=75 cm
r=
theta=
using one of the formulas for area
k=one half(r)(s)
75=(1/2)(r)(8)
75=4r
then you divide four by both sides
r=18.75cm
next you use the arclength formula
s=(r)theta
8=(18.75)(theta)
theta=2.34375 rads