Features of the calculation of cable-stayed systems are considered. The method of calculation of combined constructions with different type of suspension, including systems with inclined suspensions, has been applied. All bearing elements are considered to be in the elastic phase. The determination of the strain equations takes into account the longitudinal deformations of the suspensions as well as the longitudinal force arising in the bar panels. The basic matrix equation for determining the horizontal and vertical movements of all components of the structure has been obtained for the cantilever cable-stayed system. This is a mathematical model of the system. It allows you to determine the state of the structure at the current time. This means that it opens the way to regulating the stress-strain state. Calculation and variant modeling of system nodes also becomes possible.