Question

See Picture. It has to do with circle radius. Please help me. This will be quick.

Answer 1

help

Answer 2

I can't see circle b

Answer 3

You need find the radius of circle b

Answer 4

\[C_A=3A_B\]
\[C=2πr;\quad A=πr^2\]
\[C_A=2πr_A;\quad A_b=πr_B^2\]
\[2πr_A=3πr_B^2\]

Answer 5

But I can't see it! Is it important!

Answer 6

you make up a circle b n find radius

Answer 7

\[r_A=27/2\]

Answer 8

circumference of circle A is
\[27\pi\]

Answer 9

so area of circle B is one third of that, namely
\[9\pi\]

Answer 10

so we know
\[9\pi=\pi r^2\]solving for r tells us
\[r=3\]

Answer 11

\[2π\times {27 \over 2}=3πr_B^2\]
\[27/3=r_B^2\]
\[9=r_B^2\]
\[r_B=3\]

Answer 12

rb=3

Answer 13

i have to add that this is a very silly and misleading question. the
\[27\pi\] is a length, whereas the
\[9\pi\] is an area, they live in different dimensions. second one is in square units

Answer 14

y is there a pi symbol after every answer

Answer 15

?

Answer 16

the radius you are looking for does not inlude the number pi. it is just 3

Answer 17

so the radius of Circle be is?

Answer 18

3 in

Answer 19

I meant 3 cm

Answer 20

k and R U EXTREMELY POSSITIVELY SURE!!

Answer 21

I cant afoord to lose points on this QUIZ

Answer 22

oh hold on..

Answer 23

yes 99%

Answer 24

it has to be above 101%

Answer 25

y is it not 4.5 cm.

Answer 26

?

Answer 27

that is imposible.. even einstein could not say that..

Answer 28

what is impossible?

Answer 29

101%

Answer 30

k fine it must be 100%

Answer 31

now why can't it be 4.5 cm., the radius?

Answer 32

Is is already solved by unkleraukus at the above..

Answer 33

do u know the formulae @Anikate

Answer 34

yup

Answer 35

not memorized tho