Respuesta :
Both a and b can be the answer since you can eliminate a variable using both of them. The answer is below
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For this case we have the following system equations:
[tex]x + 2y = 11\\6x + 4y = 34[/tex]
To use the elimination method we must multiply the first by -2. So:
[tex]-2x-4y = -22\\6x + 4y = 34[/tex]
In this way, if we add the equations, the variable y is eliminated.
Answer:
-2
Option C