Answer
$$
\begin{aligned}
& F=798 \mathrm{lb} \\
& 67.9^{\circ}\\
& x=7.43 \mathrm{ft}
\end{aligned}
$$
Work Step by Step
$$
\begin{aligned}
& \pm F_{R_x}=\Sigma F_x ; \quad F_{R_{\mathrm{s}}}=-500\left(\frac{4}{5}\right)+260\left(\frac{5}{13}\right)=-300 \mathrm{lb}=300 \mathrm{lb} \leftarrow \\
& +\uparrow F_{R,}=\Sigma F_y ; \quad F_{R,}=-500\left(\frac{3}{5}\right)-200-260\left(\frac{12}{13}\right)=-740 \mathrm{lb}=740 \mathrm{lb} \downarrow \\
& F=\sqrt{(-300)^2+(-740)^2}=798 \mathrm{lb} \\
& \theta=\tan ^{-1}\left(\frac{740}{300}\right)=67.9^{\circ} \text { } \\
& ↻+M_{R A}=\Sigma M_A ; \quad 740(x)=500\left(\frac{3}{5}\right)(5)+200(8)+260\left(\frac{12}{13}\right)(10) \\
& 740(x)=5500 \\
& x=7.43 \mathrm{ft} \\
&
\end{aligned}
$$
