As part of a question on axial load I need to simplify two equations in terms of P ( and ). http://img207.imageshack.us/img207/5757/77260215.png [Broken] In the above you can see how FBA and FBC were simplified to 0.8081P and 0.7143P respectively. I understand both the section prior to this and the one after, though I do not understand how this simplification was carried out. Any help would be greatly appreciated. Thanks.