#1

ok, so im on the very last question for homework, and i have no clue how to solve it, so naturally i come to the pit for help. here it is.

In a circle, a 90 degrees sector has area 36 pi in. squared. What is the circle's radius?

In a circle, a 90 degrees sector has area 36 pi in. squared. What is the circle's radius?

#2

a full circle is 360 degrees, so 90 is 1/4 of that. Therefore the area of the circle is 36x4 pi in.^2

A=pixradius^2 so Radius= square root of (A/pi)

A=pixradius^2 so Radius= square root of (A/pi)

#3

Multiply by four.

Divide by two.

???

EDIT: oh yeah you find the square root

Divide by two.

???

EDIT: oh yeah you find the square root

#4

a=r(theta)

r = (36 pi) / (90, which you have to convert to radians)

I believe that's how you solve it.

Pre-calc/Trig, no?

r = (36 pi) / (90, which you have to convert to radians)

I believe that's how you solve it.

Pre-calc/Trig, no?

#5

well, 90 degrees is 1/4 a circle. so in theory, 4(36pi)=the circumference. Now just plug that into whatever forumla you are using.

Above user: I was trying to do it without converting. Although, his angle would be pi/2 i believe.

Above user: I was trying to do it without converting. Although, his angle would be pi/2 i believe.

#6

a=r(theta)

r = (36 pi) / (90, which you have to convert to radians)

I believe that's how you solve it.

Pre-calc/Trig, no?

That is the easier way to solve it, but it is the same as mine.

#7

Above user: I was trying to do it without converting. Although, his angle would be pi/2 i believe.

Yeah, pi/2 would be right.

I was going to have him solve that part

That is the easier way to solve it, but it is the same as mine.

True. Your way relies more on knowing what you're talking about than mine, which is just an equation I memorized.

*Last edited by Beware!Criminal at Apr 1, 2008,*

#8

well, 90 degrees is 1/4 a circle. so in theory, 4(36pi)=the circumference. Now just plug that into whatever forumla you are using.

Above user: I was trying to do it without converting. Although, his angle would be pi/2 i believe.

4x(area of sector) would = the total area not the circumference

The way that I posted is the way to do it without converting, and the dude who posted above is posting the advanced way to do it.

#9

alright cool, thx for the help guys. i can finally go to bed now

#10

wow you actually do your math homework. i applauded you

#11

not only should we applaud him but also the fact that you can go on ug for math help cheers to you all