Answers:
i) It can graze an area of approximately 961.625 square meters
ii) The ungrazed area is roughly 802.375 square meters
note: I used pi = 3.14 which is approximate; if you want more accuracy, use more decimal digits in pi
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Step-by-step explanation:
Check out the attached image below for a visual diagram.
The area of a circle is the formula
A = pi*r^2
Use r = 35 as the radius and pi = 3.14 as the approximation for pi, to get,
A = pi*r^2
A = 3.14*35^2
A = 3846.5
Then divide this by 4 to get the area of a quarter circle
A/4 = 3846.5/4 = 961.625
This is the approximate area the horse can graze
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Subtract this from 42^2 = 42*42 = 1764 because this is the area of the entire square. Doing this will get you the ungrazed area
Ungrazed area = (entire plot) - (grazed area)
Ungrazed area = (entire area of square) - (area of quarter circle)
Ungrazed area = 1764 - 961.625
Ungrazed area = 802.375