Math Help for Section 8.2, Page 394

Common Error
Mistakes are often made during the first step of the Method of
Elimination. When multiplying an equation by a constant to obtain
opposite coefficients, be sure to perform the same operation on each side of the
equation. For instance, when solving for y in the system of equations

    $
\left\{ \eqalign{ -6x+2y=&-8
&{\small\color{red}\quad\quad\text{Equation 1}}
\cr 3x+5y=&16
&{\small\color{red}\quad\quad\text{Equation 2}} \cr} \right.
$

the following step is incorrect because only the left side of
Equation 2 is multiplied by 2.

Here is the correct way to solve for y.