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moongazer
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
http://s43.photobucket.com/albums/e364/bloome74/?action=view¤t=Cow.png
could you check my answer i got 4950pi ft^2
Could you show your solutions if I got a wrong answer :)
I used the formula of 1/4 of a circle :)
You computed for 4 areas right? then added it :)
Actually you should use area of a sector, where angle is Pi/4.
ohhh, so it is better to use the area of sector formula?
I tried it and it is the same :)
Area of sector is ( Theta/2) x r^2. WHere theta is in radians.
http://www.wolframalpha.com/input/?i=pi%2F4%28100%5E2%2B40%5E2%2B50%5E2%2B30%5E2%29
@ganeshie8 Thanks, I made an arithmetic error with the area with radius 40 :)
@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 :)
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
@Champs @ganeshie8 Thanks to both of you. :)
yup ! good thinking !! yw :)
It is better to use area of sector otherwise you'd face problem when the angle is not =90 deg.
@Champs oh. That makes sense. Thanks for the reminder I will remember that. :) I'll also try to solve this with area of sector. :)
@Moongazer what is your answer for that problem? Thanks.