Question 484092
I think you have a typo in your submission.
Instead of:
x +2=9
-x+3y=11 
.
You probably meant:
x +2y=9
-x+3y=11 
.
Using the "addition" method we combine both equations together:
x +2y=9
-x+3y=11 
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   5y=20
    y=4  
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We substitute the above into:
x +2y=9
x +2(4)=9
x +8=9
x = 1
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Solution:(x,y) = (1,4)