Question

http://oi40.tinypic.com/301dco5.jpg
Need help finding 10 and 12 Please and Thank You
Help me get the formula because when I type in 36.8=260/360*2*pi*r I don't get the correct answer which suppose to be 8.1 for number10

Answer 1

for 12.) you see that r = 4 is 1/2 the length of the side of the square

Answer 2

s = r*(theta) but theata has to be in radians

Answer 3

The 36.8 cm is the length of the longer arc

Answer 4

in that case 260/360 * 2* pi *r = 36.8

Answer 5

260 degrees * Pi/180 = 260pi/180 = 13pi/9

Answer 6

So \[r = \frac{ 36.8 }{ \frac{ 13\pi }{ 9 } }\]

Answer 7

This is 8.1

Answer 8

For number 12:
The sides of the square are 8 so we have 8 + 8 + 8 = 24 and now we need half of the circumference. The circumference is 2 * pi * 4 = 8 pi so half of it is 4pi

The total perimeter = 24 + 4pi

Answer 9

In converting from degrees to radians you multiply by pi/180 which = 1 (so you aren't changing things)

So that's where the 180 came from

Answer 10

Alrighty Thank You very much.