Hey There!
First, you would distribute.
By distribute I am implying that you would multiply the outside numbers by the inside numbers.
Furthermore, you would subtract the lower variable.
2(n-3)
2n - 6 = 4n + 1
Since 2n is the lower variable you would subtract it.
4n - 2n = 2n
2n + 1 = -6
-6 -1 = -7
n= -7/2