Question

1. which method is best for solving the system of linear equations shown?

\\(\

$$\begin{cases} y = x - 15 \\\\ 4x - 5y = 63 \\end{cases}$$

\\)
substitution
elimination
graphing

Explanation:

One of the equations ($y = x - 15$) is already solved for $y$. Substitution method involves replacing a variable in one equation with its expression from another equation. Here, we can substitute $y$ in the second equation ($4x - 5y = 63$) with $x - 15$ directly, which simplifies the process. Elimination would require manipulating equations to eliminate a variable, and graphing is less precise and more time - consuming for solving. So substitution is the best method.

Answer:

A. substitution