Answer:
[tex](4;3)[/tex]
Step-by-step explanation:
Add the two equations together
[tex]I+II: x+7y+2x-7y=25-13 \rightarrow 3x=12\rightarrow x =4[/tex]
At this point i'd rather replace x=4 in the first equation to get [tex]4+7y=25 \rightarrow 7y=21 \rightarrow y=3[/tex]
To keep eliminating you multiply the first by 2 and subtract the second
[tex]2\times I -II: 2x+14y-2x-(-7y)=50-(-13)\rightarrow 21y=63 \rightarrow y=3[/tex]
