theta = atan(3/4);
F = 5.5;

A = [1 0 sind(theta) 0 0 0 0 0;...
    0 1 cosd(theta) 1 0 0 0 0;...
    0 0 cosd(theta) 0 cosd(theta) 0 0 0;...
    0 0 0 0 0 1 0 0;...
    0 0 0 1 0 0 1 0;...
    0 0 0 0 cosd(theta) 0 1 0;...
    0 0 0 0 cosd(theta) 0 0 1;...
    0 0 0 0 0 0 0 0];
%B = [RAy RAx NAd NAb NDc NDb NBc RCy]';
C = [0 0 0 -F 0 0 0 0]';
inv(A)*C