Chapter 8.2, Problem 2CVC

Fill in each blank so that the resulting statement is true.

Consider the following system:

$\{\begin{array}{c}x+y-z=-1\text{Equation}\text{1}\\ 2x-2y-5z=7\text{Equation}2\\ 4x+y-\text{}\text{}2z=7.\text{Equation}\text{3}\end{array}$

We can eliminate. x from Equations 1 and 2 by multiplying Equation 1 by ____ and adding equations. We can eliminate x front Equations 1 and 3 by multiplying Equation 1 by _____ and adding equations.