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jennyf

x + 4y = 14   /(*-1)

x + 11y = 35

 

-x-4y=-14

x+11y=35

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0+7y=21

 

7y=21

y=21/7=3

 

y=3

 

x+11y=35

x+11*3=35

x=35-33=2

 

x=2