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

A = [0 1 cos(theta) 1 0 0 0 0;...
    1 0 sin(theta) 0 0 0 0 0;...
    0 0 0 -1 0 0 1 0;...
    0 0 0 0 0 -1 0 0;...
    0 0 0 0 -cos(theta) 0 -1 0;...
    0 0 0 0 sin(theta) 0 0 1;...
    0 0 -cos(theta) 0 cos(theta) 0 0 0;...
    0 0 -sin(theta) 0 -sin(theta) -1 0 0];

%B = [RAy RAx NAd NAb NDc NDb NBc RCy]';
C = [0 0 0 0 0 0 0 F]';
inv(A)*C