Question

A cow is tethered by a 100-ft rope to the inside corner of an L-shaped building, as show in the figure. Find the area that the cow can graze.
a=20, b=50, c=100, d=60, e=50

Answer 1

http://s43.photobucket.com/albums/e364/bloome74/?action=view&current=Cow.png

Answer 2

could you check my answer i got 4950pi ft^2

Answer 3

Could you show your solutions if I got a wrong answer :)

Answer 4

I used the formula of 1/4 of a circle :)

Answer 5

That's correct.

Answer 6

Thanks! :)

Answer 7

You computed for 4 areas right? then added it :)

Answer 8

Actually you should use area of a sector, where angle is Pi/4.

Answer 9

Sorry Pi/2..:P

Answer 10

ohhh, so it is better to use the area of sector formula?

Answer 11

I tried it and it is the same :)

Answer 12

Area of sector is ( Theta/2) x r^2. WHere theta is in radians.

Answer 13

Well done..:)

Answer 14

http://www.wolframalpha.com/input/?i=pi%2F4%28100%5E2%2B40%5E2%2B50%5E2%2B30%5E2%29

Answer 15

@ganeshie8 Thanks, I made an arithmetic error with the area with radius 40 :)

Answer 16

okay :)

Answer 17

@Champs Which do you think is the better thing to use (although the result will be the same) ? area of sector formula or area of 1/4 of a circle?
please explain :)

Answer 18

@ganeshie8

Answer 19

hmm i have used 1/4 of circle area as it looked obvious at first glance.

but as you said it is same thing as sector formula eh ?
in sector formula we multiply the area by a factor of : \(\frac{\pi/2}{2\pi} \) = 1/4

both sector formula and area of 1/4 of a circle give the same factor :P

Answer 20

@Champs @ganeshie8 Thanks to both of you. :)

Answer 21

yup ! good thinking !! yw :)

Answer 22

It is better to use area of sector otherwise you'd face problem when the angle is not =90 deg.

Answer 23

You are welcome.:)

Answer 24

@Champs oh. That makes sense. Thanks for the reminder I will remember that. :)
I'll also try to solve this with area of sector. :)

Answer 25

@Moongazer what is your answer for that problem? Thanks.