Determine the second moments of area in in4 and the radii of gyration in inches for the shaded section shown about the x-axis and the y-axis. Solution Given that , y2 = x Total width along x-axis - 25 inches and along y it is 5 inches dA = xdy= y 2da = Integration(y2da) = Integration {y4dy }=[ y 5/5 ]05 Ix=625in4 dIy =1/3 bh3 = 1/3 x3dy=1/3 y 6dy =integration [1/3 y 6]50 =[y7/21]50 Iy=3720.23 inches4.