The system of the equation doesn't give the solution at (-3, -6).
-4x+y = 6
solve for y
[tex]-4x+y =6\\y= 6+4x[/tex]
5x-y =21
substitute the value of y in equation 2,
[tex]5x-(6+4x) =21\\5x -6 -4x =21\\5x -4x=21+6\\x = 27[/tex]
Substitute the value of x in equation 2,
[tex]5x-y =21\\5(27)-y =21\\135-y = 21\\-y=21-135\\-y = -114\\y=114[/tex]
We can see that the solution of the two equations is at (27, 114). Also, it can be verified by plotting the line on the graph.
Hence, the system of the equation doesn't give the solution at (-3, -6).
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