Question 214652
How do I solve by addition method? 

7x-5y=11 
3x+y=-11
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1st, the coefficients of one of the variables must be equal.  Multiply the 2nd eqn by 5 
15x+5y = -55
7x -5y = 11
------------  Add them
22x = -44
x = -2
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Sub for x into either eqn
3*(-2) + y = -11
-6 + y = -11
y = -5
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