S ={ (2,-2) }
1) Let's solve that linear system of equations, by the Elimination Method:
3x + y = 4 Add both equations simultaneously
2 x - y = 6
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5x = 10
x = 2
2) Now we can plug the quantity of x= 2 into the simplest equation:
2x -y = 6 Plug into that
2(2) -y = 6 Multiply it
4 - y = 6 Subtract 4 from both sides
-y = 6 -4
-y = 2
y= -2
3) Hence, the ordered pair that verifies this Linear Equation is (2,-2)
The product of 2 and -2 yields -4