Hi, can you please help me with case number 7? I don't know how to solve it

please select the 'bottom center' of the given cross section as an origin of your reference axis. Then calculate

1. location of the centroid,(x,y)
2. moments of inertia, Ix(in^4)
3. radius of gyration,rx

1 - 76 DOUBLE ANGLES Two equal leg angles Properties of sections Wt. Area AXIS X-X AXIS Y-Y per Ft of 2 Radii of Gyration Angles Angles Designation S Angles Angles Back to Back of in Contact Separated Angles, In. Fy= Fy = Fy = Fy In. In. 3/4 36 ksi 50 ksi 36 ksi 50 ks L 8x8x1% 113.8 33.5 195.0 35.1 2.42 2.41 3.42 3.55 3.69 102.0 30.0 177.0 31.6 2.44 2.37 3.40 3.53 3.67 90.0 26.5 159.0 28.0 2.45 2.32 3.38 3.51 3.64 77.8 22.9 139.0 24.4 2.47 2.28 3.36 3.49 3.62 N SXN 65.4 19.2 118.0 20.6 2.49 2.23 3.34 3.47 3.60 .997 .935 52.8 15.5 97.3 16.7 2.50 2.19 3.32 3.45 3.58 .995 .921 .911 .834 L 6x6x1 74.8 22.0 70.9 17.1 1.80 1.86 2.59 2.73 2.87 x 66.2 19.5 63.8 15.3 1.81 1.82 2.70 2.85 57.4 16.9 56.3 13.3 1.83 1.78 2.68 2.82 48.4 48.3 11.3 1.84 1.73 2.66 2.80 39.2 11.5 39.8 9.23 1.86 1.68 2.51 2.64 2.78 29.8 .961 8.72 30.8 7.06 1.88 1.64 2.49 2.62 2.75 .995 .921 .911 .83 L 5x5x 7% 54.4 16.0 35.5 10.3 1.49 1.57 2.16 2.30 2.45 47.2 13.9 31.5 9.06 1.51 1.52 2.14 2.28 2.42 32.4 9.50 22.5 6.31 1.54 1.43 2.10 2.24 2.38 24.6 7.22 17.5 4.84 1.56 1.39 2.09 2.22 2.35 .982 .919 5/16 20.6 6.05 14.8 4.08 1.37 2.08 2.21 2.34 .995 .921 .911 .834 L 4x4x % 37.0 10.9 15.3 5.62 1.19 1.27 1.88 2.03 31.4 9.22 13.3 4.80 1.86 2.00 25.6 7.50 11.1 3.95 1.22 1.18 1.83 1.98 19.6 5.72 8.72 3.05 1.23 1.14 1.68 1.81 1.95 16.4 4.80 7.43 2.58 1.24 1.12 1.80 1.94 .997 .935 13.2 3.88 6.08 2.09 1.25 1.09 1.66 1.79 1.93 .995 .921 .911 .834 Where no value of Q, is shown, the angles comply with the noncompact section criteria of Specifica- tion Sect. B5.1 and may be considered fully effective. For Fy = 36 ksi: For Fy = 50 ksi: Cc = 126.1/VQ C: = 107.0/VQ, AMERICAN INSTITUTE OF STEEL CONSTRUCTIONof plate to be to top chord he roof truss sure I . Existing Roof Truss Section One Steel Plate Equal Double Angles & Plate Case No L- Shape Plate Size [ 8 x x x 1 10 0 2" Two Equal LaXOX L S $ 5 x 1 Back to Back 14 x 4 x 1 1 3 x 3 x 1 1 2 x 2 x /4 [ 8 * 8 x 1 [6XOX Figure 2 : Proposed modification 1 4 x 4 x 1 [ 3 * 3 x 1/4 6 " x 1/2 Page 1 of