Question - Combing the three equations, \(\sqrt{((\frac{σ_z-σ_x}{2})^2+τ_{xz}^2))} -\frac{σ_z+σ_x}{2} sinφ=c cosφ\), \(\frac{∂σ_x}{∂x}+\frac{∂τ_{xz}}{∂z}=0\), and \(\frac{∂τ_{xz}}{∂x}+\frac{∂σ_x}{∂z}+γ=0\), lead to the equation called ___________