Question 5.86: Determine the normal reaction at the roller A and horizontal...

Equations of Equilibrium: The normal reaction N_A can be obtained directly by summing moments about point B.

\hookrightarrow + \Sigma M_A=0 ; \quad 10\left(0.6+1.2 \cos 60^{\circ}\right)+6(0.4)-N_A\left(1.2+1.2 \cos 60^{\circ}\right)=0

N_A=8.00  \mathrm{kN}

+→ \Sigma F_x=0 ; \quad B_x-6 \cos 30^{\circ}=0 \quad B_x=5.20  \mathrm{kN}

+↑ \Sigma F_y=0 ; \quad B_y+8.00-6 \sin 30^{\circ}-10=0

B_y=5.00  \mathrm{kN}