Sdenotes the length of the arc of a circle of radius r subtended by the central angle theta. find the missing quantity. thetaequalsone fourth radian, sequals3 feet, requals?

The appropriate relation is ...

... s = rθ

Filling in the given information, you get ...

... 3 ft = r·(1/4)

Multiply by 4 and you find r:

... 12 ft = r

you would use (d.) the law of cosines or a^2 = b^2 + c^2 – 2bc(cos a)

, b^2 = a^2 + c^2 – 2ac(cos b), or c^2 = a^2 + b^2 - 2ab(cos c). you wouldn't use b. the law of sines as it is mostly effective when 1side and 2angles are given. a and c aren't the answer for they are the improper versions of the law of cosines. hope this is .