Question

Solve each system of linear equations using the elimination method:3x-y=92x-y=7

Answer 1

Subtracting the second equation from the first one we get:

$\begin{gathered} 3x-y-(2x-y)=9-7, \\ 3x-y-2x+y=2, \\ x=2. \end{gathered}$

Substituting x=2 in the first equation and solving for y we get:

$\begin{gathered} 3(2)-y=9, \\ 6-y=9, \\ -y=3, \\ y=-3. \end{gathered}$

Answer: x=2 and y=-3.