Which of the following best summarizes the reason why we must write both equations in standard form (ax + by = c) and align like terms vertically before we can perform the elimination method?

You are given the system: y = 4x - 3 and 6x + 2y = 20. Which method: substitution or elimination, would be considered the most efficient to solve this system of equations and why?

Use elimination to solve the system 5x + 2y = 13 and 8x − 7y = −6 by multiplying each equation by the other's x-coefficient. What is the final solution?

A student attempted to solve the system 5x − 2y = 13 and −10x + 4y = −26 by elimination and concluded there are infinitely many solutions. Examine their reasoning and determine whether their conclusion is valid. Show the algebra.

Solve by elimination: $3(x+2y)=21$ and $4x-5y=1$. What is the final solution?