Question 245344
That can't be solved.
It says 3x-y is 4, and is 0.
That's inconsistent.
If you graph it, you get parallel lines, no intersection, no solution.
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Substitution:
3x - y = 4

3x - y = 0 --> y = 3x
Sub for y into 1st eqn:
3x - 3x = 4
0 = 4
It doesn't.