Which method is most efficient in solving a system of linear equations when two equations have x values with opposite coiffiecent values?

Elimination

Step-by-step explanation:

A system of equations is 2 or more equations for which the same x, y solution exists. We can solve the system in three ways: elimination, substitution, or graphing. Elimination is the best method when we have standard form equations and x values with opposite coefficients. This is so because the x variable will eliminate easily and allow us to solve for y.