Total Weight of Each Member
$W_{AB} = 50(12) = 600 ~ \text{lb}$
$W_{CE} = 50(12) = 600 ~ \text{lb}$
$W_{DF} = 50\sqrt{8^2 + 6^2} = 500 ~ \text{lb}$
From the FBD for Member CE
$\Sigma M_C = 0$
$8D_V = 6(600) + 12(2000)$
$D_V = 3\,450 ~ \text{lb}$
$\Sigma F_H = 0$
$D_H = C_H$
$\Sigma M_D = 0$
$8C_V + 2(600) = 4(2000)$
$C_V = 850 ~ \text{lb}$
From the FBD for Member DF
$\Sigma M_F = 0$
$6D_H = 4(500) + 8(3450)$
$D_H = 4933.33 ~ \text{lb}$
$\therefore \, C_H = 4933.33 ~ \text{lb}$
$\Sigma F_H = 0$
$F_H = D_H$
$F_H = 4\,933.33 ~ \text{lb}$
$\Sigma F_V = 0$
$F_V = 500 + 3450$
$F_V = 3950 ~ \text{lb}$
Checking:
From the FBD of the whole system
$\Sigma M_B = 0$
$12R_A = 4(500) + 6(600) + 12(2000)$
$R_A = 2466.67 ~ \text{lb}$
$\Sigma F_H = 0$
$B_H = R_A$
$B_H = 2466.67 ~ \text{lb}$
$\Sigma F_V = 0$
$B_V = 600 + 500 + 600 + 2000$
$B_V = 3700 ~ \text{lb}$
From the FBD of Member AB
$\Sigma F_H = 0$
$2\,466.67 + 4\,933.33 - 2\,466.67 - 4\,933.33 = 0$ (okay!)
$\Sigma F_V = 0$
$3\,700 + 850 - 600 - 3\,950 = 0$ (okay!)
