Question

if arc AB measures 155 degrees (14 cm), what is the length of the radius of the circle, to the nearest hundredth? drawing.........

Answer 1

my teacher says the answer is 5.71 (the radius)

Answer 2

...i just dont know how to solve it

Answer 3

http://en.wikipedia.org/wiki/Arc_(geometry)
\[\frac{arc degree}{360}=\frac{arclength}{circumference}\]

http://en.wikipedia.org/wiki/Arc_(geometry)
\[\frac{arc degree}{360}=\frac{arclength}{circumference}\]
\[\frac{155}{360}=\frac{14}{2\pi*r}\]

Using cross multiplication:
\[155*2\pi*r=14*360\]

Solve for r. Note: I got 5.17, so someone wrote it down wrong (either you or the teacher!)

Answer 4

lol i was just going to ask if i could cross multiply

Answer 5

omg thanks.