If you would like to solve the system of equations n = 3m + 6 and n - 2m = 2, you can do this using the following steps:
n = 3m + 6
n - 2m = 2
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n - 2m = 2
3m + 6 - 2m = 2
m = 2 - 6
m = -4
n = 3m + 6 = 3 * (-4) + 6 = -12 + 6 = -6
(m, n) = (-4, -6)
The correct result would be (-4, -6).