Support Reactions
$R = \frac{1}{2}(135 \times 7) = 472.5 ~ \text{kN}$
From the Section to the Left of N-N
$\Sigma M_G = 0$
$10.5(\frac{25}{\sqrt{634}}F_{DF}) + 22.5(472.5) = 15(135) + 7.5(135)$
$F_{DF} = -728.40 ~ \text{kN}$
$F_{DF} = 728.40 ~ \text{kN compression}$ answer
$\Sigma M_D = 0$
$9.6F_{EG} + 7.5(135) = 15(472.5)$
$F_{EG} = 632.81 ~ \text{kN tension}$ answer
$\Sigma F_V = 0$
$\frac{32}{\sqrt{1649}}F_{DG} + 2(135) = 472.5 + \frac{3}{\sqrt{634}}F_{DF}$
$\frac{32}{\sqrt{1649}}F_{DG} + 270 = 472.5 + \frac{3}{\sqrt{634}}(-728.40)$
$F_{DG} = 146.84 ~ \text{kN tension}$ answer
Checking:
$\Sigma F_H = 0$
$F_{EG} + \frac{25}{\sqrt{1649}}F_{DG} + \frac{25}{\sqrt{634}}F_{DF} = 0$
$632.81 + \frac{25}{\sqrt{1649}}(146.84) + \frac{25}{\sqrt{634}}(-728.40) = 0$
$0 = 0$ (check!)