Watch carefully:
2N = 8
Divide each side of the equation by 2:
N = 4
2n + 8 = -142n = -22n = -11
If 'n' is 8, then (2n - 7) is 9 .
2(4) = 8
2n+2n equals 4n
if you mean 2n=8, then N=4, which translate to 2x4=8
Nonsense.
2n plus 7 equals 19 2n equals 12 n equals 6
Substituting n=4 into the expression 25 - 2n, we get 25 - 2(4) = 25 - 8 = 17.
If En = 2n then E9 = 2*9 = 18
If n = 9 then 2n must be 18.
Un = 2n - 8 Un = 2n - 8 Un = 2n - 8 Un = 2n - 8
an=8-2n