Find the are of the circle and subtract the area of the circle from the area of the square. use the diameter to find the length of one side of the square
A=s*s A=68*68 A=4624 square feet r=34 feet A=πr*r A=3.14*34*34 A=3.14*1156 A=3629.84 square feet 4624-3629.84=994.16 994.16 square feet of the field will not be irrigated.