anonymous one year ago Solve using S=r(theta) Radius Central Angle Arc length ? pi/3 3/2 m

1. anonymous

its 3/2=pi/3(r) i dont know how to find r

2. anonymous

3. anonymous

i obviously know that i have to get r by itself but i dont know how cause the pi is confusing me.

4. anonymous

@jim_thompson5910

5. anonymous

@jim_thompson5910

6. jim_thompson5910

so you want to solve $\Large \frac{3}{2} = \frac{\pi}{3}r$ for r?

7. jim_thompson5910

if so, multiply both sides by the reciprocal of pi/3 $\Large \Large \frac{3}{2} = \frac{\pi}{3}r$ $\Large \Large \color{red}{\frac{3}{\pi}}*\frac{3}{2} = \color{red}{\frac{3}{\pi}}*\frac{\pi}{3}r$

8. anonymous

i just keep getting a decimal.

9. anonymous

oooooooooo..... 9/2pi

10. jim_thompson5910

yeah I'd leave it as a fraction and leave it in terms of pi

11. anonymous

$\pi d=\text{circumfrence}$$\pi 2 r=\text{circumfrence}$$\frac{\pi 2 r}{6}=\frac{\text{circumfrence}}{6}$$\frac{\pi 2 r}{6}=\frac{3}{2}$Solve for r.

12. jim_thompson5910

$\Large r = \frac{9}{2\pi}$

13. anonymous

That is what Mathematica calculated.