a horse is tethered to one corner of a rectangular grassy field 42 m by 26 m with a rope 16 m long . over how much area of the field can it graze ?
"area of the shaded portion = 1 ⁄ 4 × π × ( 16 ) 2 = 201 m 2 answer c"
divide(multiply(power(16, const_2), const_pi), const_4)