For an arch length s, area of sector A, and central angle θ of a circle of radius r, find the indicated quantity for the given valuer=55.8 cm, θ= pi\12 radians.

For an arch length s area of sector A and central angle θ of a circle of radius r find the indicated quantity for the given valuer558 cm θ pi12 radians class=


Answer :

Hello!

First, let's write some important information:

• arch length,: s

,

• area of the sector,: A

,

• central angle θ,: π/12 rad

,

• radius r,: 55.8cm

To obtain the area of sector A, we must use the formula below:

[tex]A=\frac{r^2\cdot\theta}{2}[/tex]

As we know some values, let's replace them:

[tex]A=\frac{55.8^2\cdot\frac{\pi}{12}}{2}=\frac{3113.64\cdot\frac{\pi}{12}}{2}=\frac{\frac{3113.64\pi}{12}}{2}=\frac{259.47\pi}{2}=129.735\pi[/tex]

To finish, we must replace the value of π and solve the multiplication:

Note: I'll consider π = 3.1415 (approximated value).

[tex]\begin{gathered} A=129.735\cdot\pi \\ A=129.735\cdot3.1415 \\ A\cong407.56 \end{gathered}[/tex]

The most approximated answer is alternative A. 407.575cm².