2 × 3 pangkat x+1 -9x + 7 = 0

2.3^(x+1) - 9^x + 7 = 0
2.3^x . 3 - 3^2x + 7 = 0
6.3^x -(3^x)^2 + 7 = 0

misalkan 3^x = a
6a -a^2 + 7 = 0
a^2 -6a - 7 = 0
(a-7)(a+1) = 0

a = 7
3^x = 7
x = 3'log7

atau
a = -1
3^x = -1
tidak memenuhi

Hp = { 3'logx}