Question 759645
3x + 12y = 9
x = -4y - 3 

Then:

3x + 12y = 9
x +4y = -3

If we multiply the 2nd equation by -3 we have :

3x + 12y = 9
-3x -12y = 9

Adding them:

0x+0y = 18 (not true)

Answer: The system has no solution 


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