To use the equation we need a1 and d(the common difference). We have a1 = 57, we need to find d. 93-84 = 9; 84-75=9; 75-66=9; 66-57=9 d = 9 a350 = 57 + (350-1)(9) a350 = 57 + (349)(9) a350 = 57 + 3141 a350 = 3198
we know that diameter=2radius or diameter/2=radius so 12=diameter 12/2=radius=6 subsitute area=π(6)^2 area=36π divide 36π by 8 36π/8=18π/4=9π/2π=4.5π area of one section is 4.5π square feet or if we aprox pito 3.14159 then we get 4.5(3.14159)=area=14.1372 square feet or 14.14 square feet