Final answer:
The question provided is incomplete for solving by elimination as it contains only one equation. Additional equations are needed to perform elimination. The fragments suggest calculations related to concentrations or motion but do not directly apply to the question's system of equations.
Step-by-step explanation:
To solve the system by elimination, we would usually need at least two equations with an equal number of variables. Unfortunately, only one equation is provided: x + 5y - 4z = -10. To solve a system using elimination, each variable would need to be eliminated one by one by combining two or more equations.
Based on the given fragments that talk about substituting and using the quadratic equation, it appears we are dealing within a context that involves chemistry or physics where these substitution methods and quadratic equations are often used for calculation of concentrations and motion respectively.
The information provided seems to be mixed, likely from different contexts, so it is difficult to give a step-by-step solution for solving the original equation without additional data or equations.