Question

Please Help with answering a question on area of circle. Will fan and medal!

Answer 1

What is the area of a sgment of 60 deg?
what is th earea of an equilateral triangle?

that will give you the area of the unshaded section

subtract that from area of whole circle to get your answer

Answer 2

169.6 is the area of the sector

Answer 3

324 pi is the area of the circle..

Answer 4

the area of the triangle is 140.3

Answer 5

im lost.. idk how this matches up with the answer choices.

Answer 6

it may help if you leave teh area of the equilateral triangle as

sqrt3 * r^2/4

Answer 7

https://www.google.co.uk/#q=area+of+equilateral+triangle

Answer 8

?? i get what you're saying but that still doesn't match up

Answer 9

I haven't done the solution- but you can see the sqrt(3) appearing there.

I think if oyu rearrange teh sums it may come out to one of those options

Answer 10

im still confused. like i understand what you're doing but i dont know what to do next.

Answer 11

area of sector = pi r^2 /6
area of triangle = sqrt3 * r^2/4
area of circle = pi r^2

See if you can manipulate that - I haven't time ot do all the detail

Answer 12

@mathmale @sleepyjess @phi @Preetha

Answer 13

See if YOU can manipulate that

I am fairly sure the answer is there

why call on all the others?

Answer 14

You said you didnt have time and i'm still confused. I was just trying to get help quickly.

Answer 15

area of sector = pi 18^2 /6
area of triangle = sqrt3 * 18^2/4
area of circle = pi 18^2

Answer 16

? now what

Answer 17

so the shaded area is
area of circle - ( area of segment - area of triangle)

I have worked it through- and if you put the numbers above (leaving pi in place) you can get to one of the answers with simple arithmetic

Answer 18

(be careful with the - sign in the brackets)

Answer 19

The main way to do maths is to DO maths

the above is now an exercise in solving an equation

Answer 20

pi*18^2- ( pi*18^2/6- sqrt. 3 * 18^2/4)

Answer 21

now what?

Answer 22

put the terms in th brackets over a common denominator of 24

Answer 23

thats not going to give me one of the answer choices..

Answer 24

or

probably easier to take the common factor of 18^2 out of LL terms... first

Answer 25

I promise it WILL if oyu follow through what is now just arithmetic..

Answer 26

pi*18^2- ( pi*18^2/6- sqrt. 3 * 18^2/4)

what i do with the 18^2.. you arent making sense to me.