We have
[tex]
\begin{cases}
2x+4y=20\Longrightarrow x+2y=10\\
3x+2y=26\\
\end{cases}
[/tex]
Then multiply the second equation by -1 to get
[tex]
\begin{cases}
x+2y=10\\
-3x-2y=-26\\
\end{cases}
[/tex]
Now add the equations that way you eliminate y-terms. You find that
[tex]-2x=-16\Longrightarrow x=8[/tex]
Now plug in the x to either of the original equations and solve for y.
[tex]
x+2y=10\\
8+2y=10\\
2y=2\Longrightarrow y=1
[/tex]
The solution is the intersection of two lines at [tex]P(8,1)[/tex].
Hope this helps.
