## moongazer 3 years ago 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

1. moongazer
2. moongazer

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

3. moongazer

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

4. moongazer

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

5. Champs

That's correct.

6. moongazer

Thanks! :)

7. moongazer

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

8. Champs

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

9. Champs

Sorry Pi/2..:P

10. moongazer

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

11. moongazer

I tried it and it is the same :)

12. Champs

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

13. Champs

Well done..:)

14. ganeshie8
15. moongazer

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

16. ganeshie8

okay :)

17. moongazer

@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 :)

18. moongazer

@ganeshie8

19. ganeshie8

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

20. moongazer

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

21. ganeshie8

yup ! good thinking !! yw :)

22. Champs

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

23. Champs

You are welcome.:)

24. moongazer

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

25. Kenneth05