## anonymous 4 years ago Find the length of an arc of 40° in a circle with an 8 inch radius.

1. Hero

associated picture?

2. amistre64

arc length is just a portion of circumference

3. anonymous

thnxx=) and no pic included

4. amistre64

circumference = angle * r, any arc length is angle * r

5. amistre64

turn the angle to rads tho

6. Hero

Yeah, amistre has it. I was thinking about something else.

7. amistre64

40 needs a pi, so 40*pi/180 = rads

8. amistre64

9. Hero

amistre, general formulas and approaches are always welcome

10. amistre64

id have to think like a pigeon then; and i tend to think on the fly lol

11. anonymous

i dnt get it answer choices are 8/9 , 16/9 or 64/9

12. amistre64

$Arc_{length}=\frac{degree*pi*radius}{180}$

13. amistre64

I get 8/9 pi when I do it

14. anonymous

thnxx

15. amistre64

40*8 = 320 320 32 16 --- = -- = -- pi; i mighta inputed it wrong in me calculator; let me dbl chk 180 18 9

16. amistre64

1 7/9 = 16/9 got it right that time lol

17. anonymous

lol ok

18. Hero

In general, when finding the arc length of a circle when given the radius and degree, you may use the following formula: $\frac{\theta}{360°} = \frac{x}{2 \pi r}$ , x = arc length

19. anonymous

thnxx guys